Rob Rohde-Szudy has a nice article over at Duckworks Magazine outlining making your own composting toilet. Composting (or dry) toilets are all the rage for the marine world I think... given the growing limits on dumping and waste removal, having a toilet that has not holding tank, no pumpouts, etc. might be just the thing.

Sun-mar and others make commercial units, but something like this might work really well for me on my boat. What I didn't see outlined is what you do with the toilet paper... anybody know? read more »

Here's a good, workman like way of getting on (or under) the water.

Tao Xiangli prepares his homemade submarine before operating it in a lake on the outskirts of Beijing September 3, 2009. Amateur inventor Tao, 34, made a fully functional submarine, which has a periscope, depth control tanks, electric motors, manometer, and two propellers, from old oil barrels and tools which he bought at a second-hand market. He took 2 years to invent and test the submarine which costs 30,000 yuan (US$4,385).