SAN MATEO, Calif. — Chad Hurley and Steve Chen have some experience with turning a small Web site into Internet gold. In 2006 they sold their scrappy start-up YouTube to Google for $1.65 billion.

More recently they picked an unlikely candidate to be their next Web sensation: a Yahoo castoff.

The men are trying to inject new life into Delicious, a social bookmarking service that, in its time, was popular among the technorati, but failed to catch on with a broader audience.

“What we plan to do,” Mr. Hurley said in an interview here last week, “is try to introduce Delicious to the rest of the world.”

Created in 2003, Delicious lets people save links from around the Web and organize them using a simple tagging system, assigning keywords like “neuroscience” or “recipes.” It was praised for the way it allowed easy sharing of those topical links. The site’s early popularity spurred Yahoo to snap it up in 2005 — but in the years after that Yahoo did little with it.