Only 2 days in, the 1HDC is off to a sensational start, with inspiring ideas (and some pretty nice sketches!) on ways to save water in the bathroom. Catching our eye:
Most "duh" simple, elegant, and low-tech: melovescookies's Bucket. Gonna take a lot to top that one.
On the high-tech side, we've got rkuchinsky's SignSmartShower, where the jets are directed solely at the contours of the body--no overspray:
For the most subversive, check out skforlee's Decoy Drain, where a trompe l'oei drain acts as a cover, flooding the stall and forcing your roommates to cut their shower short: