Space Invaders - Another clone of the classic game

A .NET version of the classic game.  It's all written in C# and uses GDI+ (not DirectX) for graphics.  If I do any more work on this it'll probably be to port it to DirectX and add a few of the remaining features needed to do everything the original did (e.g. aliens move down, shields, etc.).  Feel free to do as you wish with the source and if you have any feedback on how to do things in a better way, definitely send them my way. 

Screenshot:

 

Download: [Executable] --- [Source]