Five Fingers (Toes, actually)
A recent article about Vibram Five Fingers, appeared in Time, and apparently Mexico's Tarahumara Indians routinely ran ultra-marathons wearing only thin rubber sandals or no shoes at all (experts urge caution before chucking your Asics). The American Academy of Physical Medicine & Rehabilitation concluded that "running in shoes exerts more stress on the knee, hip and ankle than does running barefoot or walking in high heels" (per the article)...interesting.
I think they would be great for sailing and rowing...or walks on the beach. I'm going to pick up a pair, and I'll let you know what I think. I'm not sure if I can get used to having all that material between my toes, but we shall see.
Photos via Five Fingers facebook site.