Developing apps for Windows Phone 7? Fancy a chance to win a WP7 new device worth around $500? Of course you do! You can by entering into the WP7 User Group Event sweepstake. It's simple to enter and there's a bonus too - the more apps you develop and enter into the stake, the more chance you have of winning.
Simply develop apps, submit them into the Marketplace and then fill out the form (you can add five apps maximum per form submission). You will need to use the event code (which is required on the form): VIL12. They're also running a competition featuring a prize of free advertising with 25,000 impressions, neat eh? Please note that both are US only.
Source: WP7 User Group Event