Team Rat King will try to participate in this honorable event once again!
As I (ratking) seem to have forgotten everything about any other tool (like Flash, Haxe, or Visual Studio), I will use Unity as game engine with the language C# for scripting. My own base code, which consists of some helper classes (partly stuff written myself, partly stuff copied from the Unify wiki or other places, plus iTween, plus some useful shaders) and a very simple rigidbody-based character controller, will hopefully make the development faster so I can concentrate on the actual gameplay. I might include cInput 2.
My partner, ratqueen, will probably do the graphics, with Photoshop and 3dsmax.
If there will be any sound, we will use Audacity, sfxr and/or whatever generates some interesting notes.
Good luck and much fun to all entrants!