sixwaves6 Waves has shown that new entrants can still break into the Facebook apps market. And because of that, the Hong Kong company has been able to raise $17.5 million in a round of funding from Insight Venture Partners.

The company has more than 141 applications that have attracted 44 million monthly active users on Facebook, according to AppData. A year ago, it had 60 apps and 22 million users, says Inside Facebook. The company has built its audience by creating simple knock-offs such as Gangster Wars, launching them in multiple languages, and cross promoting apps.

The funding shows that the game isn’t over in social games.  Some have referred to Zynga, Playfish and Playdom as the Big Three of social games, implying that they’re running away with the market. But as my former colleague Eric Eldon noted in a discussion with theMix Agency last night, new entrants are making headway. After a couple of years of effort, Crowdstar has surpassed Playfish in numbers of Facebook users, and 6 Waves has been climbing the charts as well. These companies operate their games as services, continuously updating them even after launch to make sure that they spread in a viral way.

The company has 18 employees and may expand beyond Hong Kong.

Be sure to check out our latest announcements on GamesBeat@GDC, our video game conference taking place March 10 in San Francisco.