"SpongeBob SquarePants," "South Park" and "Punk'd" are among 14 popular TV shows now available for download from the iTunes media service under a new agreement between Apple Computer Inc. (AAPL) and Viacom Inc.'s (VIA) MTV Networks, the companies said Thursday.

The agreement bolsters Apple's market-leading iTunes service as an alternative conduit for television programming, adding a range of shows from children's animated hit "Dora the Explorer" to the violent and often vulgar "Jackass."

Like others on iTunes, the programs will cost $1.99 each.

Videos downloaded from the iTunes Music Store can be played back on a personal computer or an Apple iPod portable music player. Some 8 million have been downloaded since videos were added to the online store late last year.

Walt Disney Co. (DIS) was the first media company to make a deal with Apple to sell video on iTunes in October, starting with episodes of such hits as "Desperate Housewives" and "Lost." NBC Universal (GE) followed in December, with "Law & Order," "The Tonight Show with Jay Leno" and others.

Under the new agreement, Viacom's MTV Networks will also offer shows including practical joke show "Punk'd," "Stand-Up" — a program from its Comedy Central network — and reality programs "Laguna Beach" and "Real World/Road Rules Challenge: Gauntlet 2."