Microsoft today kicked off the GDC the Dream-Build-Play game development contest, open to any user of XNA Game Studio Express. The top prize is $10,000 and the opportunity to have your game published on Xbox Live Arcade. The contest ends July 2, 2007, and winners will be announced August 13 at Microsoft Gamefest 2007 in Seattle. Microsoft also noted that "more than 20 winners" will be selected to win additional prizes totalling a value of more than $40,000 from Microsoft, Alienware, AMD, Autodesk and Softimage. Microsoft said in a press release that its "investments in game development technologies are helping to spark a new creative era while ensuring the best games are being built for Microsoft platforms."