Do-it-yourself social network platform GROU.PS has raised $1 million in the second tranche of its first round of funding. The new money comes from Golden Horn Ventures, the same firm that invested $1.1 million in the startup roughly a year ago. VentureBeat reports that GROU.PS’ more than 100 million registered users have created about 40,000 groups—though the majority of its users are outside the U.S. The S.F.-based startup faces stiff competition: Ning is the most well-known of the create-your-own social media platforms, with over 200,000 active networks; there’s also KickApps, which lets users create widget-based networks.