Orchestral Version

A Video Game tune, sometimes the Background Music, is turned into a huge orchestral version by the game developers. (Or, in some cases, another band.) It is almost-never used within the game or series and is only available online or in stores.

This is usually done because the game itself has limitations on the quality of the music if it is an 8-bit, 16-bit, etc. game.

The music is not always the same thing, and is sometimes extended. It may also be worse than the original music depending on who you talk to.

Not always limited to video game music, but is rarely seen in other media.

Not to be confused with Orchestral Bombing. See also Boss Remix.

Action Adventure

 * The Legend of Zelda with most songs.

Adventure Game

 * The original Leisure Suit Larry theme song was composed for the PC speaker - which can only produce single-tone sine waves. For the seventh game they redid it as a full-blown professional jazz recording.
 * The sax was played by none other than Larry Laffer's spiritual father: Al Lowe. Get the intro from here, and all of the other tunes from the game(s).

Fighting Game

 * Super Smash Bros. The soundtracks for Melee and Brawl do this for lots of older Nintendo themes.
 * Also a literal orchestra version. Several of the Melee themes have been performed by the New Japan Philharmonic Orchestra and released as an album called Smashing...Live!.

Platform Game

 * Super Mario Bros. The main theme especially gets this treatment, considering how well known it is.
 * Super Mario Galaxy 2 contains orchestral arrangements for the Bowser level and main level tunes from Super Mario 64.
 * Lately, the Sonic the Hedgehog series has been using orchestral rock mixes of the games' main themes as backing music for the Final Boss fights.
 * Sonic the Hedgehog 2006: "His World".
 * Sonic Unleashed: "Endless Possibilities."
 * Sonic Colors: "Reach for the Stars."

Role Playing Game

 * Final Fantasy games get this a lot. Square Enix has released orchestral albums of Final Fantasy I and II and Final Fantasy VI, and there are several CD's based on orchestral concerts.
 * Final Fantasy VII in particular - I think there's an orchestral version of virtually the entire soundtrack...
 * Orchestrated themes for the actual game soundtrack are pretty commonplace for the series post-VII.
 * The original MOTHER had a soundtrack CD that, rather than containing the NES games' eight bit melodies, reproduced them as fully orchestrated and vocal songs.
 * Tropers may know its first song, "Pollyanna," from the fact that it's the official unofficial theme song of the Sugar Wiki.
 * Overclocked Remix has Chrono Symphonic, a retelling of Chrono Trigger's soundtrack entirely in orchestrations.
 * The original soundtrack for Dragon Quest VIII was fairly normal, but in the US release, every track was replaced with an orchestrated version of the original.

Shoot Em Up

 * The fans of the Touhou Project are quite fond of making orchestral remixes of ZUN's already awesome music.

Sports Game

 * The famous fight theme for Punch-Out!! was completely redone by a rock band (with awesome horn section) for the Wii remake.

Visual Novel

 * Ace Attorney.

Anime

 * Suzumiya Haruhi no Gensou. Aya Hirano and Minori Chihara actually gave the vocals for four of the songs performed ("Bouken Desho Desho", "God Knows", "Lost My Music", and "Yuki Muon Madobe Nite").
 * In Magical Girl Lyrical Nanoha, one of Nanoha's Leitmotifs, "Raising Heart, Set-Up!", was later updated with "Raising Heart, Set Up! (The Magical Orchestra)". When The Movie came, another Orchestral Version of the song was created, and one of the the Limited Edition DVD/Blu-Ray bonuses show that they hired an actual orchestra to perform it along with other similar updates to the Season 1 soundtrack.

Theatre

 * The original cast album of Styne, Comden and Green's semi-musical play Say, Darling replaced much of the two-piano accompaniment used in the production with orchestrations by Sid Ramin. Ramin and his then-uncredited assistant Robert Ginzler went on to orchestrate Jule Styne's next musical, Gypsy.
 * The original off-Broadway production of Assassins was done without a real orchestra, but Stephen Sondheim's score was orchestrated for the original cast album.

Web Original

 * The Angry Video Game Nerd's theme tune has an orchestral version floating around on YouTube, by the fans. It was later used in his videos.

Real Life

 * There exist quite a number of traveling productions that exclusively perform re-orchestrated versions of video game songs. The most notable ones are probably Video Games Live and PLAY!.