I brush my teeth at the sink, as I only shower once a day.
This ties in to a funny story from last week..... I was helping sell merchandise at a Carbon Leaf concert, and I discovered their lead singer brushes his teeth wherever he can sit down and get into his backpack. He couldn't get into the dressing room area for some reason, so he wandered over to the merchandise booth, sat down, pulled out his toothbrush and paste. He then proceeded to brush without water, and I guess swallowing the toothpaste. The worst part was when someone walked up to buy merch and he wandered over to talk, putting the toothbrush down where he'd been sitting. Then promptly sat on the brush, pulled it out from under himself, and started brushing again.
Yeah, rock stars, what heart throbs.