My plan was to have a bucket with a single bit of string going across. On top of that I had a square bit of card lightly stuck to the string. On there i had a nice chunk of bread. When the mouse went on to the platform it would unbalance it and he would get tipped into the bucket.
1 night later i checked my bucket and blamo "1 r t3h w1n0r"
Here he is close up:

And below is my trap fully in shot.