While studios and audiences alike have been slow to embrace the burgeoning video-on-demand business, SightSound Technologies has unveiled plans to offer 20 new feature films a week on its Web site, SightSound.com. Netco, which already offers Miramax’s 1999 release “Guinevere” and has a deal for 12 more Miramax titles in the future, has added titles from the recently defunct Destination Films banner, including “Eye of the Beholder,” starring Ashley Judd, which debuted on the site Friday. Other Destination pics include B.O. flops “Drowning Mona,” “Bats,” “Whipped” and “Thomas and the Magic Railroad.”Under the SightSound system, a viewer buys a key that allows a file to be downloaded onto his computer and then played using the Microsoft Media Player software. Netizens pay $3.95 for a two-day rental. Offerings on the site will include episodes of the Comedy Central animated series “South Park,” as well as other indie films. SightSound has been offering consumers the chance to download pics for more than two years, beginning with Darren Aronofsky’s “Pi” in 1999. Where its system once delivered movies solely to PCs, SightSound’s technology now can digitally deliver pics to theaters and portable PocketPCs.