I have no personal experience with any of these products, but as a long-time camper I've seen a similar product in catalogs for years:

http://www.freshette.com/

No affiliation, etc.

Could be interesting for biking. Being out in the middle of nowhere and struggling with sweaty spandex is not generally my idea of fun. If this (or a similar) gadget would make that process a little easier and less messy I'd be all for it.