Merlin Mann of 43folders has a great list of uses for your cameraphone. Merlin calls his camera phone a “ubiquitous capture device, recording ephemeral information and visual documentation wherever and whenever it’s needed.”
Top of the list is “Remember where you parked”. Incidentally, this is the number one use for my Palm Treo 650 smartphone’s camera. In fact I hardly ever forget my parking space any more, even in the most labryinthine of basement parking facilities.