I playing with the idea of building a ROV.
A ROV is a Remotely Operated underwater Vehicle.
I plan to start simple, with a webcam connected to a computer, and 3 motors with propellers controlled by switches, all of it strapped to a frame of sealed plastic tubes. Something close to this instructable.
But the robot geek in me wont stop there! I want to build:
A moisture sensor (to warn if the electronics compartment has sprung a leak)