Yet another social game developer has raised a big round. 6 Waves, which is behind popular Facebook games like Crazy Office, has raised $17.5 million in a funding round led by Insight Venture Partners, according to Inside Facebook. The company claims that games it has created in-house and those it distributes on behalf of developers reach more than 50 million users a month. The funding follows other big rounds at rivals Zynga, Playdom and RockYou. We reached out to co-founder Rex Ng, a former Yahoo (NSDQ: YHOO) product manager, earlier today but did not hear back. InsideFacebook says that 6 Waves, which is based in Hong Kong, is thinking about opening operations in the U.S., Singapore and Taiwan.