The real estate bust wasn't kind to Roost , which started out as a real estate search engine . But CEO Alex Chang took the $8 million he raised in late 2008 and convinced his investors to back him down a completely different path: a service for creating and managing social media marketing campaigns for local businesses. Roost relaunched in the middle of last year, first going after the 25,000 real estate agents who used the original Roost. Then last March, Chang opened up Roost to other local businesses. Roost taps into Facebook and Twitter, and helps restaurants, auto dealers, non-profits and others create social media campaigns in 20 minutes on a Sunday night.