OhCrap, you've been cut off from your friends, perhaps while performing a LastStand, and have been captured by the enemy. You escape, but how can you prove you're a good guy when the bad guys have been trying to infiltrate your organization, perhaps using [[MuggedForDisguise stolen]] or [[MasterOfDisguise faked uniforms]]?

Alternately, what happens if, once you make your escape, you need to prove your identity to the local chapter of your friendly neighborhood LaResistance or your own [[HeroesRUs backing organization]], but due to the nature of your business, you don't exactly carry company ID cards on you?

And of course, sometimes you're in a club that likes to be have something akin to a SecretHandshake, in which case this can become SeriousBusiness indeed.

Why, then you need a MembershipToken! This token is something discreet, yet distinctive, that you use to identify yourself to your fellows but isn't readily familiar to outsiders. It might be some rare or specific item (possibly even some sort of MacGuffin) that not just anyone would have, or something more common but otherwise difficult to get, such as one of a relatively small set of coins with a distinct design.

See also CallingCard and MyCard. Can overlap with IconicItem for some of the more famous examples.

----
!!Examples:

[[foldercontrol]]

[[folder: Anime ]]

* In ''RevolutionaryGirlUtena,'' the ring with the rose crest instantly identifies Utena as a Rose Duelist to her fellow Duelists, and [[CoolKey allows entry]] to the Secret Forest. But Utena herself no knowledge of the purpose of the ring; she had been carrying it for years as a [[MementoMacGuffin memento of her prince]], who said it would [[BatmanGambit lead her back to him]]. Though the the true meaning of the ring is... [[{{Deconstruction}} complicated]].
* State alchemists, in ''Manga/FullmetalAlchemist'', receive specially designed silver pocket watches upon their accreditation. They can show these to non-alchemist members of the military as needed to do almost anything - ride trains without other identification, access their bank accounts, and so on.

[[/folder]]

[[folder: Film ]]

* ''Film/PiratesOfTheCaribbean'':
** The "Nine Pieces of Whatever We Have in Our Pockets" from ''Pirates of The Caribbean: At World's End.''
** From the ''Curse of the Black Pearl'', the gold coins from the cursed treasure. Elizabeth Swan unwittingly convinced the Black Pearl's crew that she was Bootstrap Bill's daughter because she had his coin, along with claiming Will's last name (in order to prevent them from realizing she was [[ThePresidentsDaughter the Governor's daughter]]).
* It's subtle, but in ''Film/IronMan'', both [[Comicbook/WarMachine Rhodey]] and Tony Stark wear the "Brass Rat", the class ring of MIT, though no particular attention is drawn to it.
* The guys in Chris Cutter's curling team in ''Film/MenWithBrooms'' all have beaver tattoos. [[spoiler:As does [[UnluckyChildhoodFriend Amy]]]].
* In the sadly [[VideoGameMoviesSuck unappreciated]] ''Film/WingCommander'' movie, Taggart is able to earn the trust of the ''[[CoolShip Tiger Claw's]]'' captain because he has [[spoiler:an [[MilitaryAcademy Annapolis]] class ring, from the [[WorldWarTwo Class of 1942]], specifically a family heirloom of Admiral Tolwyn's, which he would not have parted with easily, indicating that Taggart held Tolwyn's implicit trust.]] Among the setting's Pilgrims, the Pilgrims' crosses serve the same purpose.
* ''Film/TheATeam's'' Army Ranger tattoos work like this at the beginning of the movie.
* The ankh necklaces in ''Film/LogansRun'' are used by runners to identify one another.
* Used in rather the opposite way in ''Film/WildWildWest''. When Jim and Artemis meet each other for the first time, Artemis is disguised as President Grant. Jim almost immediately works out that he's fake because he's wearing a class ring from Harvard - the President went to West Point.
* The movie version of ''HuntForRedOctober'' uses this when the second officer of a ship takes a dislike to Jack Ryan disguising himself as a naval officer, until the captain points out his Naval Academy graduate ring, going on to explain how Jack was in a helicopter crash while at the Academy, and had to finish his studies while in the hospital for his entire last year.
-->'''Admiral Painter''': Now it's up to you, Charlie, but you might consider cuttin' the kid a little slack.

[[/folder]]

[[folder: Literature ]]

* E.E. "Doc" Smith's ''Literature/{{Lensman}}'' had the Lens, which glows with light when its owner touches it. It was specifically created due to the need for lawmen to identify themselves with a 'badge' that couldn't be stolen or forged by criminals.
* Randall Garrett's ''Literature/LordDarcy'' stories had King's Messengers, who had begemmed badges that glowed red for their owners. This was a ShoutOut to a Lensman's Lens.
* In one ''Literature/TheSaint'' story Simon Templar finds a dead body with a silver greyhound badge on it - the deceased was a King's Messenger.
* In Don Pendleton's ''TheExecutioner'' stories, top Mafia enforcers used aces (playing cards) to identify themselves to other Mafia members.
* In ''Literature/HarryPotterAndTheOrderOfThePhoenix'', Hermione creates special enchanted gold coins that look like Galleons for Harry to use to communicate when the [[LaResistance ''Dumbledore's Army'']] would meet to practice the forbidden Defense Against the Dark Arts techniques. They come again in ''[[Literature/HarryPotterAndTheDeathlyHallows Deathly Hallows]]'' to [[GondorCallsForAid call for aid to the members]].
* In ''One Lonely Night,'' MikeHammer finds a card cut into odd angles on the body of a gunman and shows it to his FriendOnTheForce, who explains it's used as a method of identification by communists, who change the angles on the cards to trip up spies. Before this happens, Hammer is able to use the card to infiltrate a local Communist cell.
* The {{Animorphs}} once run into a detachment of Hork-Bajir guards wearing blue armbands, fittingly called the elite Blue Band Squadron. In a later mission, Tobias notes Marco's shirt is the same color, so they rip it up and wear the bands in Hork-Bajir morph. Every Controller stays well out of their way.

[[/folder]]

[[folder: Live Action TV ]]

* On ''Series/BabylonFive'', members of the ''Anla-shok'', or as they are known to the humans, The Rangers, wear a distinct brooch showing a Minbari and a Human on either side of a large green stone. Earlier in the series, when the Rangers were a covert intelligence-gathering organization, this was used to allow them to discretely identify each other in public[[note]]also serves as a RewatchBonus as many of the earlier appearances of the Rangers on the show were subtle {{Meaningful Background Event}}s[[/note]] Once they become an overt military organization, and even later again become a form of SpacePolice, it is used as insignia on their uniforms instead.
* In ''Series/StargateSG1'', since Earth's Stargate has an Iris to prevent any unwanted travellers from coming through, potential allies are given a specially crafted box designed to leave a unique radioactive signature on the iris, alerting them that someone wants their attention. This is later phased out after allies are trusted enough to be given a remote GDO, which also lets them know ''which'' friendly wants to come through the Gate.
* In TheBBC's ''Series/RobinHood'', the outlaws have wooden tags with a bow and arrow carved on them.

[[/folder]]

[[folder: Tabletop RPG ]]

* ''Call Of Cthulhu'' supplement ''The Asylum and Other Tales'', adventure "The Asylum". Freygan's cultists have recognition symbols: small stones with thongs for wearing around the neck. They are rarely used since all nearby cult members know each other by sight.
* Dungeons And Dragons. AD&D 2 ed. has some spells working via designated tokens -- including "pass-cards" for warding spells and focus for mass [[DoppelgangerSpin mirror image]].
** In ForgottenRealms the Harpers have a symbol they use to identify each other: a small silver harp. After the Moonstars did split off, they use their own variant of the same. Cormyr has Purple Dragons' rings and commanders' rings that (aside of minor magics) allow access to restricted and magically protected areas, like the armory in Purple Dragons' barracks. Of course, these items are badges of service and possession of one by someone not entitled to this is a crime.
** Al-Quadim has a lot of secret societies with their own ways of identification; and appropriate magic, like a spell sending a distress call to the nearby fellow member, that works only on someone having a proper token.

[[/folder]]

[[folder: Video Games ]]

* A minor GottaCatchEmAll sidequest in ''Franchise/MassEffect'' had you searching the galaxy for medallions belonging to members of the League Of One, a Salarian precurser to the Spectres.
** Becomes problematic in the first game, since with biometrics in common usage and thus negating any need for these, Shepard is forced to routinely wait for people to confirm their identity, that they have Council Spectre status and they possess unlimited jurisdiction. Particularly on Noveria, where a brief stand-off ends with an embarrassed security agent admitting they're a little behind on updating their records.
* After completing the Joining ritual that enters them in the order, Grey Wardens in the ''Franchise/DragonAge'' universe are presented with the Warden's Oath, a special pendant containing [[spoiler:a drop of the blood mixture they have to drink during the Joining]]. It boosts Constitution a little. The pendant isn't mentioned again after the player character receives his/hers in ''VideoGame/DragonAgeOrigins'', however, and in fact it can be removed (and even sold) in favor of a necklace that has better attributes.
* A major portion of the plot of ''VideoGame/{{Metro 2033}}'' involves [[PlayerCharacter Artyom]] getting Hunter's Ranger token (and himself) to Polis so he can get help with the Dark Ones for his home station. By the time of [[VideoGame/MetroLastLight the sequel]], Artyom has a token of his own.
* In ''VideoGame/QuestForGloryII'', just before leaving for the enemy-controlled Rasier, the hero receives a sapphire pin from a Katta merchant for free. When inevitably captured in Rasier as part of the plot, the guards remove all your equipment except for the pin, which a fellow Katta prisoner (and leader of the resistance) identifies as a magical Pin of Friendship, which can only be seen by those who would be (or are) friends of the person wearing it. It convinces the prisoner to assist the hero in escaping.

[[/folder]]

[[folder: Web Comics ]]

* ''LackadaisyCats'' has its club pendant, often hidden under a layer of clothes, which is used to get into the speakeasy.

[[/folder]]

[[folder: Western Animation ]]

* ''WesternAnimation/AvatarTheLastAirbender'' combines this with SecretHandshake: To identify members, the Order of the White Lotus uses a special set of moves on a mah-jong style game. To play said special move, one must be in possession of a White Lotus Tile, and the tiles seem to be used as calling cards for the organization.

[[/folder]]

[[folder: Real Life ]]

* Challenge Coins date back to a squadron of American pilots during WorldWarOne. One of the pilots, fairly well-off, decided to have a set of coins minted with their squadron's name on it for his squadron mates to have as keepsakes. One of these pilots was shot down, captured, and deprived of his military identification by German troops. An artillery barrage caused enough confusion for him to escape to the Allied lines, where he was able to prove his not being a German spy only by presenting his squadron's coin to the Allied troops. Ever since then, failure to present your coin when challenged results in a severe punishment. That is to say, you [[CoolAndUnusualPunishment buying beers for everybody who has their coins]]. Failing a "Coin Check" while in a large drinking establishment can become...expensive. You can be challenged at any time. Even when you're on the toilet or in the shower. It's [[SeriousBusiness sacred tradition]].
** In the US Air Force, airmen are issued their first challenge coin, called an Airman's Coin, when they graduate Basic Training. Effectively, this means nobody in the Air Force has any excuse at all not to have a coin on them. Those who argue that they don't respond to coin checks because the coin is too important to them are CompletelyMissingThePoint (again, SeriousBusiness.)
** It is very common for specific groups within the military (ie: a particular Squadron or Company, or a group of soldiers who worked together on some endeavor) to mint coins specific to them, or to commemorate special events.
** The rules vary significantly from one unit to another. In some cases, nearly any coin will do. In other cases, it's not enough to have a coin on you. You have to have the ''senior'' coin (issued by someone of high-rank, such as a general or an admiral).
** Not everyone is a supporter or participant in this tradition. Many see it as a way for cheapskates to get unsuspecting marks to buy drinks. This is especially true when challenging troops new to a unit who have no way of knowing the rules. Some units avoid this by having the rules specifically exempt those who have not yet been given their unit-specific coin or had the rules explained to them.
** In some fields this is less likely than others. For example, this troper is an aerospace maintainer, one of the first fields along with pilots from the army air core era to practice this tradition. However her never has his coin on him. Why? It's considered foreign debris and can cause mechanical failure. So while coining may be still practiced and said coins are collected, the practice of challenging changes from unit to unit and field to field. This trope was taught that only three kinds of guys do challenges, Nonner's, cheapskates, and fresh airmens. All of which you don't want to be associated with.
* Graduates from many colleges use their class rings for this trope. People who draw attention to themselves by tapping the ring on their finger against whatever surface is available (tabletops, counters, etc.) are known as "Ring Knockers".
* Many [[TheEngineer engineers]] in the United States and Canada wear cast iron or stainless steel rings on the little finger of their writing hand. This way, whenever they use a pen or pencil, the ring will drag across the writing surface and/or bite into the skin slightly (The Iron Ring used in Canada is faceted rather than completely round, unlike the Engineer's Ring used in the US), reminding them of their [[ComesGreatResponsibility responsibility as engineers.]] Of course, the ring also helps fellow engineers identify each other when out in public.

----