This thread gets several pages worth of fiction a day, and the average quality is higher than Sturgeon's Law would suggest. (That is, more than 10% of it is worthwhile.) Particularly good for short crack, either humorous or lime, or both, but there's all kinds of stuff here. Very, very long. Bring a map, you will get lost in here.
Penguin's already got a bunch of individual recommendations listed further down the page, but pretty much everything he writes for this series is worth looking at if you like the Original Flavor. Blood and Spirit in particular is a must-read for fans of Suzuka and Arisa, and Stahlkönigin and the rest of the Steel Queen Chronicles are a treat for Vivio fans (Caramel Milk in particular contains 300% your daily recommended sugar intake). The rest is largely drabbles and one-shots, some of which is written for RadiantBeam's Lutecia/Vivio series Shadows and Sunrise, but it's all pretty entertaining stuff as long as you're not looking for a sweeping epic (Note that I'm only reviewing his Nanoha materials here; he's also got a bunch of work from other series that I haven't touched yet).
Seems like a fairly new writer who has put out a ton of fanfiction. It's all Nanoha, but whether you like action, adventure, angst, drama, or comedy (especially comedy!), there is something you'll like. His main work appears to be MGLN Crisis, of which he has two spinoffs, and another two in the works. He also has Unexpected Expectations which deals with mature subjects, and the darker Future Tense. There is also a bunch of shorts that are guaranteed to make you laugh! You can find a number of his fics on this page, and he updates often, like once a week at least.
Stories focused on the family and the friendly relationships of the cast. Plot-focused stories or light day-in-the-life stories. Pretty much anything that isn't focused on romance.My Fault by Dracis Tran.
Recommended by Golden Dragon 326
Synopsis: Vita reflects on Nanoha's accident that's flashbacked on in Striker(s). The story takes place right after the accident happens; Vita is sitting outside of the hospital room where Nanoha is lying unconscious.
Recommended by Person With Many Aliases, Night, DKN 117
Synopsis: In London, a mysterious figure is stealing Mage's Devices. Nanoha and company are sent to apprehend the culprit. Meanwhile, Arisa and Suzuka chase after their friends on their own, and end up meeting a "Ms. Testarossa"... It only gets crazier from there. Is a stealth crossover.
Synopsis: The Book of Darkness case is over, giving Nanoha and company some much-needed rest. But the peace ends abruptly as a pair of unknown mages descend on Earth, seeking a lost artifact and reigniting an ancient conflict. It's time to save the world again...
Synopsis: The conclusion to his Vivio-centric AU story (although it wasn't so when he began the series). Follows mostly the cast from A's (although Teana makes a cameo) as they try to thwart a terrorist plot. This story is the finale to his Vivio storyline, so you may want to start here.
Synopsis: "Crash" is a pilot for the B.E.S.T. Force, a force designed to test out new technologies, and "dispose" of confiscated Mass Weapons (Translation: We get to play with missiles). He's got a suit of Powered Armor, a partner with a noted resemblance to Asuka Langley, this universe's version of Coop, and seriously bad luck when it comes to machines. He's got just enough skill to survive when the Numbers Cyborgs came after him during the Jail Scaglietti Incident, but when Riot Force Six comes over to check out B.E.S.T.'s new countermeasure for Gadget Drones, Nanoha sees potential for more than just their new AI fighter... Comes with its own trailer.
Synopsis: One year after the events of Striker(s), Nanoha and crew find their battle continues. Old foes re-emerge, leading to a climactic clash with the fate of Mid-Childa, the TSAB, and Magic itself as the prize.
Somewhere approximately 50 years after all those have happened: Future Tense
Synopsis: The future went very, very wrong due to some unfortunate events. Nanoha wakes up more than 50 years after Striker(s), finding a future where everything she knew is different, with the TSAB being now a totalitarian state, led by Hayate Yagami. Many of her friends still work for the TSAB, while others have joined a resistance movement.
angelmira highly recommends this if you are into non OC story lines.
Nightzin also recommends this fic, as it is very mature and well written, with very few created characters. It has some similarities to Betrayer S, but they are just coincidences. The fic has also been completed and the author is still active as of 25/10/2013.
Pairings: Some teasing of Nove/Wendi, which gets elaborated on in Someone for Everyone, mentioned further down.
Synopsis: A sort-of spinoff/prequel of Someone for Everyone (see below). Jail wants to understand what Christmas is about... and decides that stealing it is the best way to do so. The consequences are nothing short of insane.
Synopsis: Takes place circa Force. When an excavation team uncovers lost scriptures from the Book of the Silver Cross, Yuuno gets called away from his civilian life to lend his expertise to the case, but things get really weird really fast when he finds the excavation site blown to smithereens and the Huckbein fighting... the Materials? Yeah baby, it's everyone's favorite Evil Twins from The Battle of Aces, and things are about to get very very interesting for our dear Ferret Boy...
Synopsis: Senior Enforcer Valentine Yaris wasn't looking to babysitting child prodigy Fate T. Harlaown on her first mission, but when the Lost Logia investigation proves to be more than it appeared, the child will have to learn rapidly if they hope to close the case.
Synopsis: Sette of the Numbers has been released from prison early for model behavior. With no other reasonable mission objectives, she does the only logical thing: move into the Nakajima house, and attempt to integrate into society. Key word being, 'attempt'.
Recommended by Nanya, spacemonkey37, universalperson, Faraway_2
Status: Complete, with a sequel ongoing.
Synopsis: Who dares stand between a mother and her daughter's life? Precia will do anything to achieve her goals. Even if it means accepting Fate.
A MGLN fanfic that completely reinvents the Nanoha Verse. A lot of barely-mentioned characters, including those already dead by the time we first learn about them, are engaged and fleshed out excellently.
Synopsis: In a time where Fate did not become an enforcer but a convict-turned-civilian collaborator. A world where TSAB is forgiving, but not forgiving enough to let ex-convicts into its organization. This is how her path was re-shaped.
Comments: This is one long, epic, story told from Fate's perspective detailing her life if she never had the opportunity to join the TSAB. This fic swings from light, fluffy scenes to serious discussions to heart pounding action. It's one of the best fics I have ever read.
Synopsis: Cutting corners hurt Precia once and she wasn't going to risk Alicia's last chance by doing so again. And when the Arthra encounters a distortion of time-space, things get dicey on Non Administrated Planet 97 without the TSAB to support Nanoha and Yuuno...
Comments: A well done AU in which the TSAB doesn't get involved with the Garden of Time. Also, notable for including the Takamachi family in the action. Shirou Takamachi's assassin skills shine when he bypasses threatening Wolkenritter to hold Hayate hostage.
Synopsis: A few months after StrikerS, Yuuno gets an itch to go adventuring again for old times sake and after digging up some information on the so-called 'Vault of Whispers', hops the next flight out to the Non Administrated planet said to hold it. Shame that the planet in question is Pandora.
Synopsis: The TSAB has found two new Lost Logia in a remote pocket dimension — the planet Earl and its moon. Complicating matters is that Earl is inhabited by a human civilization that seems to be tapping unknowingly into the power of the planet-sized Logia to turn girls into the strategic weapons called Otome. The TSAB dispatches its two best — Nanoha Takamichi and Fate Testarossa Harlaown — to infiltrate the school that manufactures the Otome, Garderobe Academy, in the form of its two newest students. Unfortunately, their Intelligent Devices are locked down into passive scanners to prevent them from drawing too much attention to themselves. Even so, they quickly gain the nickname "The Terrors of Garderobe". And their first trimester is barely over when Arika Yumemiya appears out of the desert to claim her own place at the school.
Synopsis: A simple meeting between two characters creates changes that snowball from a small chance encounter. The character interactions are just hilarious and very much in character for the characters involved. Plus it's one of the few fanfictions that this troper has ever seen that makes both Shiro and Genma awesome without them doing anything directly.
Recommended by SAMAS, ObssesedNuker, DKN 117, EpicFightingTroper
Synopsis: Two ships crash on Mid-Chlida through dimensional space. Unfortunately, either one of them alone represents a threat to all life on the planet. Da Orks and the Death Korps of Krieg seem to be of a like mind about the state of the planet: Kill 'em All!
Synopsis: While on Earth, Vivio overhears a comment made by Nanoha that causes her to run off and meet someone who will change her destiny. At least for the time he's on Earth. Crosses over with Kamen Rider Decade.
Synopsis: The sequel to the above fanfic. Vivio unexpectedly finds Tsukasa, who claims that he no longer needs comrades, while everyone begins to attempt to cast the destroyer out of Nanoha's World once again.
Synopsis: Fifteen year-old Nanoha isn't just the TSAB's Ace of Aces; she's also the reincarnation of Princess Serenity, and the Sailor Senshi desperately need her power to break a precarious stalemate with the Dark Kingdom that's been going on for over a year without Sailor Moon's help. There's just one small problem; Nanoha is newly crippled and still recovering from her timeskip injuries, but if the Senshi ask for her help she'll give it regardless of what it may cost her. Luckily Fate and Arf are around to stop the Senshi from bothering Nanoha while she's on medical leave, but when Beryl gets wind of Serenity's return and the Senshi mistake Fate for a witch keeping their Princess under a spell... well, there's really only one way this can end.
Synopsis: In the great city of Tokyo, Ranma and Genma Saotome arrive at the Tendo Dojo to fulfill Genma's dream of joining the twin schools of Anything Goes Martial Arts. That's great, but Ranma has much more pressing issues than romance, like the fact that he turns into a magical girl when splashed with cold water, or the fact that he's best friends with the ghost of that same magical girl and is very interested in remedying that whole "ghost" thing...
Synopsis: The main characters of Neon Genesis Evangelion take the powers fanon has tended to give them to the extreme and morph into physical manifestations of the Warhammer 40,000Warp Gods. As they break into the multiverse, they meet up with Nanoha and the TSAB; chaos ensues.
Synopsis: What if Nanoha's mother was really a certain sorceress known for destructive magic usage? Earth and Mid-Childa will never be the same again. Or much less said mother's home universe. That's right, her mother is none other than Lina Inverse.
Synopsis: Nanoha finds herself stranded on a Death World of ash and fire, her only companion a baby with burning red eyes and jet-black skin. Still recovering from injuries sustained prior to her arrival, taking the child to the safety of a nearby village takes nearly all of her strength and magic ability. As she recovers, she teaches the rapidly-growing child and leaves a lasting impression on him. This child is Vulkan, future Primarch of the Salamanders, and Nanoha's love will have a big impact on the 31st Millennium.
Synopsis: A new teacher arrives in Nanoha's class: a boy her own age named Negi Springfield, one of an entire society of mages that the TSAB is only now figuring out is hiding under their noses. Hilarity, of course, Ensues. Set after A's, and goes for Original Flavor.
Synopsis: Precia Testarossa's use of the Jewel Seeds causes more damage to the dimensional walls surrounding Earth than anyone could've expected. Now magical girls from across time and space have gathered. Forging new allegiances and battling new foes. Set up. Go!
Synopsis: A crossover with Evangelion. Mostly with Nanoha characters and some Evangelion characters. The year is 2015 and young Nanoha has just been chosen to become a Magical Girl by NERV as she is on the verge of puberty, the perfect time to become a Magical Girl. Follow Nanoha, Fate, Hayate, Shamal, Signum, and Vita as they try to protect Tokyo-3 and the Earth from the Invading Angels.
Synopsis: To anyone familiar with Top Gear, it's pretty much Exactly What It Says on the Tin. For those not familiar with Top Gear, it's best described as Jeremy Clarkson, Richard Hammond, and James May go to Mid-Childa, get their hands on some local cars and faff about.
Synopsis: After the JS Incident, Nanoha goes to Earth on sick leave, only to meet Dumbledore, looking for a new Defense professor. Set right after Strikers, and during fifth year. It's Nanoha at her absolute best- as a hellmaster instructor of future aces. Complete.
Synopsis: It was just a small wish: To live with their master and their friends as those uneventful days passed by, to see him grow up as he chased his ideals by his own strength. To become an ally of justice; a hero who can save everyone.
Comments: A story in which the Book Of Darkness binds itself to Emiya Shirou instead of Yagami Hayate. A interesting idea with a good deal of potential, and a greater amount of work put into it. Even though it is still in its infancy, it delivers some well-done character interactions. The initial development of the Wolkenritter's feelings towards Shirou as their master is truly endearing and heartwarming.
Synopsis: Following a Lost Logia incident on Unadministrated World 82 "Jetter" : Special Lost Property Division Six is reformed, ostensibly for Yuuno's Lost Logia hunt, but secretly to handle a new, JS related prophecy.
Comments: Through excellent writing this crossover blends quite tastefully and the Sci Fi traits from both series bring forth much plot potential.
Synopsis: Harry Dresden would honestly have been happier if that Takamachi woman had never walked into his office and asked for his help. But, well, she did, and it's technically not her fault that they're BOTH running for their lives now...
Comments: It has an interesting premise and the crossover elements are very well handled. The author has done an excellent job of merging the different magic systems.
Synopsis: A Nanoha / Puella Magi Madoka Magicacrossover. Not all destruction comes from Logia. The Nanoha crew find a destructive force that is the combined evil side of the wishes of mankind; and a group of girls about to succumb to despair in fighting it. The Power of Friendship is good; and More Dakka is good....but is it enough?
Synopsis: Nanoha's search for the Jewel Seeds has started attracting attention from the types of people interested in that kind of thing (blowing up a giant tree in the middle of town tends to do that). Because of that, one Soma Cruz has been dispatched to Uminari City. But Alucard is not the only entity interested in the Jewel Seeds...
Synopsis: The feelings of those left behind can be as strong as those of the ones who pass into the future; Arisa and Suzuka are forced to come face to face with those feelings when Nanoha's world forces itself into theirs.
Pairing: Chrono/HAREM effect (or at least that's what the summary says)
Synopsis: The story of Chrono The Blue Breaker, his rise through the military, his allies, enemies, family, friends and...other. Divided into four parts, a prologue and one part for each of the three seasons, although not even the first part has yet reached completion (despite already being over 110,000 words long).
Synopsis: A four-chapter story. "Nanoha and Fate visit Yuuno at his current assignment: identifying various Lost Logia. One of them is accidentally activated leading to results none of them expected. And to a situation that would scar Yuuno for a long time..."
Pairing: Nanoha/Fate (Under The Table), Signum/Shamal (Pink On Blonde)
Synopsis: Two stories, tied together. Under The Table shows a funny little interaction between Nanoha & Fate during a meeting, as well as the aftermath conversation between Fate and Signum. Pink On Blonde shows a peek at Signum and Shamal's end of the story.
Someone for Everyone by TheShinySword (Receives more frequent updates on the Animesuki Nanoha Fanfiction Thread)
Synopsis: Post-StrikerS. Nanoha has a relationship problem, and seeks the help of a psychologist. But it's not your normal brand of relationship problems, and for Nanoha, that means taking it Up to Eleven and beyond.
Synopsis: A fantasy Alternate Universe Fic with Nanoha as a princess and Fate as a knight who apparently betrayed and killed her. However, the unnamed narrator (some 500 years later) finds a letter from the traitorous knight to the princess, and realizes that their relationship was a bit more complex than what's recorded in most histories.