SpiralFrog to launch in December.

SpiralFrog, the music download destination scheduled to start its public testing phase this year, signed an agreement with Universal Music Group to make songs from the catalog of the world's largest record company legally available for free.

The deal applies to the United States and Canada, but further details of the agreements were not disclosed.

SpiralFrog CEO Robin Kent said the music and video download service will be entirely ad-supported and will not cost its users anything but their time.

"Offering young consumers an easy-to-use alternative to pirated music sites will be compelling," he said. "SpiralFrog will offer those consumers a better experience and environment than they can get from any pirate site."

All files on the service will be in Microsoft's Windows Media format and its integral digital rights management technology, which Kent said would help combat piracy and "provide peace of mind for the record labels and the artists."

Users can acquire any song or video they wish, but must view a 90-second block of advertising before the download starts. Each can be played on multiple PCs and moved to portable devices bearing the PlaysForSure logo, Microsoft's emblem indicating certain technical specifications have been met, and they can be played an unlimited number of times for a six-month period before they expire.

"Offering legally authorized audio and video downloads in an advertising-supported environment works, as our business model is based on sharing our income streams from that advertising with our content partners like Universal," Kent said.

He added that the service's target audience of ages 13-34 is "an advertiser's dream."