I've always favored the Saran Wrap over the toilet bowl trick...

1. Lift up the seat
2. Tightly cover the top of the bowl with Saran Wrap
3. Put seat back down
4. Remove the light bulb in the bathroom

When the intended target sits down to do her business she'll get a nice surprise (ESPECIALLY if its of a solid nature).

bogey - those pics are hilarious!

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