If you enter by March 16th, you still have a full month to put polish on the game. I’ve put forward Euro500 for prizes, so it’s not a huge fund, but it’s definitely getting some cool games created for the GE.
An interesting section to enter for ( especially if you are an artist ) is the No Python category – in Blender, you can create a complete game visually, without using programming. There is a reference in the link above to a tutorial that explains how to make a simple game..
If you get a chance to enter, the best of luck! A number of people could even enter as a team ( Leprechaun Launching anyone? :) )