The browser-based MMORPG Domain of Heroes may be free to play, but a percentage of in-game purchases will now go to some good causes.

According to a press release, 5% of all purchases made in Domain of Heroes will go to Child's Play or Women in Games International, depending on the player's preferences. Currently, users have raised more than $500 since the system launched.

Domain of Heroes is a text-based game that requires only a browser to play. There are currently more than 18,000 registered players who have created characters by picking from 27 classes and 30 races. You can read the full press release regarding the announcement below.

April 6, 2009 (Austin, TX) – Independent game developer Tandem Games announces the newest feature of its free-to-play web MMORPG Domain of Heroes: an integrated charity system that donates 5% of all in-game purchases to the cause of their choice.

Players can currently donate to Child’s Play (www.childsplaycharity.org ) or Women In Games International (www.womeningamesinternational.org ) through Domain of Heroes, with more charities on the way. Users have already raised over $500 in-game since the system was launched.

“It’s a great way for players to have a direct influence on where their donation dollars go, while raising awareness for game-related charities in general,” said Aaron Murray, Technical Director and Founder of Tandem Games. “Both Child's Play and WIGI are very excited to see this level of ongoing commitment from a company. We hope other companies will follow suit and share their revenue with deserving charities.”

Since launching in late 2008, Domain of Heroes has seen over 28 million PvE encounters and more than 160,000 PvP battles. Players can start their own guilds, collect millions of unique items, chat with hundreds of players at once, gamble for treasure, and experience an epic storyline while taking a quick break from work.

Domain of Heroes requires only a browser to play - no installs, downloads, or plug-ins are needed - and works with Internet Explorer, Firefox, Safari, and Opera browsers. With over 18,000 registered players, there’s never been a better time to create your own hero for free at www.DomainOfHeroes.com.