Dogster, the social network for dog owners, has raised $1 million in funding from a strong list of angel investors: Michael Parekh, Joshua Schachter, Adam Beguelin, Michael Tanne, Jim Young, Mike Jones, George Sarlo, Frank Caufield, Aydin Senkut, Robert Simon, Brad Feld, and Jeff Clavier. The two-and-a-half-year-old company is profitable based on $100,000 raised last May. It makes 95 percent of revenue from advertising and sponsorships and the rest from premium subscriptions.

With 250,000 registered users, and about a quarter of them very active on the site, Dogster CEO Ted Rheingold thinks he’s mastered the art of building social networks for adults. For example, Dogster orients itself around dogs, not people — with no requirement to share your name, your email address, or even your hometown. Some more tricks are to use lots of puns, and to be very careful about canine breed nomenclature and categorization. :)

What’s next? Lots more pets sites, says Rheingold (Catster has been live since August 2004). And why stop with pets? Other affinities and hobbies are on the way. “What we’ve cracked the nut on is how adults want to communicate online about what they’re passionate about,” he says. “There are a lot of things that aren’t Adult FriendFinder.” But being so specific is what’s kept Dogster from being lumped into the hypefest; branching out is a whole different ballgame.