Short Attention Span Theater, or SAST, was a show which ran briefly on Comedy Central in 1991-1992. It was co-hosted by Jon Stewart and Patty Rosborough and consisted of clips of short comedy sketches or standup acts separated by banter from the hosts. The sketch clips were generally of skits from existing comedy shows (like Kids in the Hall), while the standup clips covered a range of comedians.
The name Short Attention Span Theater is now popularly used to refer to any activity catering to those with the attention spans of gnats. Ironically, since the title has remained in circulation substantially longer than the show did, many people1 who use the term seem to have no idea that it was ever an actual television show.
1 - Three examples:
http://www.wired.com/wired/archive/5.07/streetcred.html?pg=2
http://www.salon.com/tech/feature/1999/07/21/short_films/
http://pw1.netcom.com/~gscale/susanwg/cmindware/shortAttention.htm