CORE77.COM FAST TRACK TO THE MOBILE APP CONTEST
Here's a pretty cool contest for you.
http://fasttrackapp.core77.com/ - core77 online design magazine is having a contest for App Designers - not developers - for Windows Phone apps. The apps do not need to be coded out, but the Design of the UI should be solid.
Note this is a DESIGNER contest. Entries only need to have images of key screens. The owners of the contest specifically mention and advocate for SketchFlow as well. You can even enter Photoshop mockups.
The theme for this contest is productivity. Note this is a DESIGN challenge. Read about the specifics of what the judges will be looking for in the designs at http://fasttrackapp.core77.com/judging . Developers - Share this with your designer buddies!