Everyone knows that pistons can control water, but I just had to do a little "proof of concept" using the 1.7 piston features, once they were integrated into SerenityMC.net's server. So here's a tiny little project that took about an hour and a half to complete.

This is on the edge of my "Epic Valley" area, a collection of projects of large scale.

The technical details: it's a very simple lever-to-piston arrangement, but packing ten pistons inside the small space (and keeping the redstone dry) was the challenge I wanted to hit. It was fun.