Another product that I haven't personally tried is the Ratsack (http://www.armoredoutdoorgear.com
), which isn't bearproof, but is supposedly good for all other critters.
April '05 our group used 4 Ratsacks in the Canyon with perfect results.
While on this trip we conducted a scientific test, wereby we put a Ratsack (full of various foodstuffs) INSIDE of a 2 gallon ziploc bag and left it unattended for 5 days *.
Upon inspection 5 days later, the ziploc was totally chewed-through but there was no damage to the ratsacks nor the food stored inside.
(* - the idea behind the ziploc was to ascertain that the stash had, in fact, been visited, and that the "critter" that visited had the means to chew through more standard bagging techniques.)