Here's me in Ratty, my home built pedal powered Mouse Boat.
Mouse boats are basically punts that can be built out of a single sheet of ply, with minimum wood working skills. We built her mostly in our upstairs back bedroom, and just finished the paint and epoxy outside. Everyone should have a go at building one! The pedal mechanism was scrounged from a commercially built pedalo thing, but had a prop, not paddle wheels...