Greatest Hit (...And 21 Other Pretty Cool Songs)

Greatest Hit (...And 21 Other Pretty Cool Songs) is a compilation album by American progressive metal band Dream Theater, released in Australia on March 29, 2008, and by Rhino Records in the United States on April 1. The title alludes to their only top 10 radio hit, "Pull Me Under." It features three songs from their breakthrough album, Images and Words, remixed by Kevin Shirley: "Pull Me Under," "Take the Time," and "Another Day." The compilation also includes "To Live Forever," a re-recording from the Awake era of a song originally from the Images and Words sessions (previously featured as a B-side of the single "Lie"), which had not been released on a full-length album. Several single edits of popular Dream Theater songs are also included.

The tracks are divided into two discs: the first, titled "The Dark Side," features heavy, metal-influenced songs, while the second, "The Light Side," highlights the band's melodic side. The collection spans the years 1991 to 2005 and, as a result, does not include any songs from Dream Theater's debut album, When Dream and Day Unite, their A Change of Seasons EP (despite its 1995 release), or their 2007 album, Systematic Chaos.

Drummer Mike Portnoy explained in the album's booklet that the song selection was carefully curated to appeal to both new listeners and longtime fans. The compilation offers alternative versions of songs from previous albums to entice newcomers to explore the band's catalog while providing existing fans with fresh takes on familiar tracks. He also remarked that a third disc, titled "The Epic Side," should have been included.