siminioff.jpgIt may take them a while, but the fabulously wealthy from Dot-com boom eventually realize they miss the action.

David Siminoff, the Silicon Valley investor who made billions in the late 1990s by making early investments in America Online, Yahoo and eBay, is the latest to return. The Capital Research investor retired after the boom, and practiced his golf game. Siminoff has dabbled only slightly in the latest Internet wave, backing for example 4INFO, a mobile search service. Now, he’s returning to join Venrock as a general partner, as part of that firm’s new $600 million fund. As Adam Lashinsky notes, he was half of one of the valley’s most prominent power couples during that first boom. His wife, Ellen Siminoff, was an early executive at Yahoo, known for being the doorkeeper for Yahoo’s deals with start-ups. She’s now chief executive of advertising company Efficient Frontier (we’d link to our profile three years ago about the couple, but it’s deeply buried in the Mercury News’s archives).

venrock.jpgSiminoff will invest in media companies. He was most recently CEO of Spark Networks, the parent of several online dating sites, including Jdate. Venrock’s latest fund will also target new alternative energy sources, it said. The firm, a 40-year-old venture arm the Rockefeller family, is also spiffing up its brand: It’s dropping the “Associates” from its name.