This Octavia blog, in all her classy glory. Features frequent guest appearances from Vinyl Scratch and Pinkie Pie.note This blog takes an interesting take on the "Octavia is Pinkie's sister" theory by making them cousins. She is also aware of the 4th wall.
Ask the Pie Sisters, a relatively short and very cute blog about the rock farming Pie sisters: Light grey-maned, blue-grey bodied Blinkie Pie; Teal-maned, light grey bodied Inkie Pie; and Mane 6 Pinkie Pie (the sisters tried using 'Pinky' as her pseudonym, but Pinkie didn't quite get the hang of it).
Moonstuck should be added as well. Imagine Ms Paint Adventures, only with "Woona" put in. With Egophiliac's fantastic art, bizarre sense of humor, and plethora of references, it certainly belongs here.
Apparently, in a post on the "Ask Molestia" blog, Echo accidentally walked in on Celestia having sex...or something. It was so horrifying, that Echo ran from the room screaming "AAGH MY POOR SIGHTLESS EYES!" Yes, Echo has been blind since birth. Apparently Molestia having sex is just that horrifying.
Ask Pia Ikea follows the Ponyville representative for IKEA. She enjoys her work so much that she counts sheep and even gives her daughter Maude The Talk in the style of furniture assembly instructions. Her cousin Maja shows up to answer questions as well.
While it's mostly a dark, story-driven blog, with some risque stuff thrown in, Ask Discord Whooves can be pretty hilarious at times, usually either when the Doctor gives snappy responses to stupid questions or encounters somepony who's not instantly won over by his charm. Or when the "pet" Miss Pinkamena gave him shows up to interrupt a routine answering-session.
Probably funny in an schadenfreude way, but in the Rarity crossover blog A Touch of Diamonds, someone suggested they bring all the Opals from their respective dimensions to play. So of course Lil' Miss Rarity brings the Pinkamena doll that has Opal's heart in it. Cue all the Opals staring in horror.