I bought this thinking that it would help me from constantly misplacing my tools. But for the kind of stuff I tend to do (Burning Man, Ephemerisle), it's too pricey to lose/fall in the water. It would probably work well for someone who works primarily out of their own shop.
http://www.ebay.com/itm/291353707745?ssPageName=STRK%3AMESELX%3AIT&_trksid=p3984.m1555.l2649
http://www.ebay.com/itm/291353707745?ssPageName=STRK%3AMESELX%3AIT&_trksid=p3984.m1555.l2649