Credits Medley

Some Closing Credits do not have their own specific background music, but rather feature a Medley of various music pieces from the movie/game.

Doesn't really count if it's just an expanded mix of just one prior music piece.

Compare the visual counterpart, the Credits Montage.

Film

 * Batman Begins and The Dark Knight.
 * All the Star Wars movies.
 * John Williams is quite fond of this. Notable example: the closing credits from Harry Potter and the Prisoner of Azkaban, which consisted of seven themes from the film back-to-back. And was awesome.
 * Conan the Barbarian by Basil Poledouris
 * The end credits of the new Star Trek movie are a mashup of the new theme ("Enterprising Young Men") and Alexander Courage's original Star Trek theme.
 * The credits music for Veggie Tales: The Ultimate Silly Song Countdown is a dance remix medley of all the songs featured in the countdown.
 * Advent Children plays a character theme medley over the credits.
 * The Back to The Future sequels, especially Part II.
 * The second sequel is more effective, featuring a suite with the film's Western theme, the love theme, and the train theme sandwiched by the main theme of the series.
 * Masters of the Universe.
 * Independence Day.
 * Star Trek VI the Undiscovered Country
 * The theatrical release of The Abyss was the first James Cameron film (but not the last) to feature double-column speeded-up end credits on account of all the people involved, so Alan Silvestri's end credit suite features "Finale," a lot of "Bud On The Ledge" and the ending of "Back On The Air"  without the choir. When it was released on video, it had a slower and one-column only roll which therefore lasted much longer, and had a much longer suite to match made up of "Finale," "The Pseudopod," "Resurrection," a reprise of the first part of "Finale" , and the excerpts from "Bud On The Ledge" and "Back On The Air."
 * Team America: World Police
 * 9 uses a medley of themes from the film, mainly Winged Beast and Burial, with a remix of The Machines at the beginning. It does not appear on the official soundtrack for some reason.
 * In all three The Lord of the Rings movies, after an Award Bait Song (and in Fellowship, a rendering of one of the Shire themes as a song), there's a mashup of music for the film, including some deleted and never heard before pieces. In the Extended Editions this is taken Up to Eleven, adding from 10 to 20 minutes of additional music over the Fan Credits.

Television

 * Skins does this at the end of season 2 to Wild World to shockingly poignant effect.

Theatre

 * Many stage musicals do this with their outmarches (also known as exit music).

Video Games

 * Neverwinter Nights.
 * Banjo-Kazooie: Nuts & Bolts features an impressive score that weaves the themes of several main areas into a monster medley as the credits are viewed. The credits include the themes to Mumbo's Test-O-Track, Log BOX 720, Terrarium of Terror, Gruntilda's Challenge, Jiggoseum, Banjo Land, Nutty Acres and Gruntilda's Final Battle.
 * The end of Final Fantasy X (pre credits) uses two of the three main themes.
 * Final Fantasy V uses a partial remix of its "Flying on the dragon" music in its end theme.
 * Final Fantasy VI deserves special mention because it manages to mix together every single character theme along with the obligatory "Prologue" music in a massive 20-minute long ending sequence.
 * Advent Children and Crisis Core have similar medleys that both begin with a remix of The Main Theme of Final Fantasy VII, which is the only time said piece of music is featured on the respective soundtracks.
 * Dissidia takes this Up to Eleven by creating a medley of the ending themes from the first ten games!
 * The prequel does the same thing, but includes ending themes from Final Fantasy XI, Final Fantasy XII, and Final Fantasy XIII as well. It is also bookended by the opening and closing bars of the song Final Fantasy at the start and end. Listen close for them.
 * All the Mega Drive Sonic the Hedgehog games did this, with the exception of Sonic 3 which had an original track instead of the usual medley. Sonic 4 does that too.
 * And then Sonic Rush Series for DS did it again.
 * The beta version of Sonic 3 actually had its own ending medley too, where it would play music from all stages in it and Sonic and Knuckles, but was very likely cut from release version due to the splitting of the game into two parts. That beta is for a game called Sonic 3 Limited Edition which would've had both games on one cart. Its not a Sonic 3 beta per se.
 * Sonic Generations does this with both versions (Play Station 3/Xbox 360/PC and 3DS).
 * The Legend of Zelda the Wind Waker.
 * The Legend of Zelda Twilight Princess as well. It's also virtually the only time you'll hear the original The Legend of Zelda theme in the game.
 * Not to mention Ocarina of Time and Majora's Mask as well.
 * Super Mario RPG and Paper Mario.
 * Super Mario Galaxy and Super Mario 64.
 * Mario Kart Wii.
 * Pokémon HeartGold and SouSilver do this in the opening.
 * The end credits of FireRed and LeafGreen as well.
 * Super Smash Bros Brawl uses the themes from each respective game in the series (64, Melee, and Brawl).
 * Wario Land 4
 * Earthbound and Mother 3, if only for the cast roll segment; the rest of the credits have individual compositions.
 * The Wario Ware series, starting with Twisted.
 * The NA version of Wild Arms 1.
 * Call of Duty: World at War combined three themes into one piece. A Heavy Metal guitar and drum kit were added on top of them, as were some techno bits accompanied by taiko drums.
 * Mario & Luigi: Bowser's Inside Story has a whole mix of the different theme tunes as the credits music, starting from Plack Beach, to parts of Cavi Cape, to parts of the underwater theme, the Dimble Wood theme and the Toad Town theme.
 * Live a Live also has a credits sequence that plays all of the main characters' leitmotifs one after another.
 * VVVVVV, with the music being the background music of various areas of the gamefield.
 * Kingdom Hearts Birth By Sleep features a medley of the three main characters' leitmotifs (Terra, Aqua, and Ventus in order), the Neverland battle theme, the three Disney Princesses' worlds' battle themes, and the game's arrangement of "Dearly Beloved".
 * Mega Man 6 credits has this.
 * Fire Emblem games frequently do this, starting as far back as the original game; more often than not, generally in conjunction with a unique composition.
 * For example, Fire Emblem: Mystery of the Emblem has Ending Medley B from Book II.
 * The DSiWare game Art Style: Pictobits ends with one, incorporating bits and pieces from all of the remixes featured in the game.
 * The credits theme of Patapon and Patapon 2 is a medley of songs introduced the games.
 * Star Fox Command.

Western Animation

 * The music that plays during the credits of the first Bionicle trilogy are all pieces of the in-movie score, though not full themes, bur rather different samples cut together in such a way, they sounds as if they were composed as standalone musical themes exclusively for the credits. Also, they're beautiful.
 * The end credits music for Disney's Dinosaur combines pieces of "The Egg Travels", "Aladar and Neera", "Breakout/It Comes With a Pool", "Raptors/Aladar Meets the Herd", and "Inner Sanctum/The Nesting Grounds".
 * The Rescuers Down Under features an excellent end credits piece using the score's main themes.