Nothing beats a sturdy 5 gallon bucket for Geo-caching. With a few of these and a shovel you can make any waypoint on your GPS a fully stocked re-supply point. This approach gives you a lot of flexibility in planning and in contents of you BOB. Only thing that can't be easily stored in this fashion is transport. (maybe a disassembled electric powered razor scooter ;-) ) Find some out of the way locations in public parks where there isn't much interest in decorative gardening and you can have 20-30 gallons of supplies 4 feet below grade in an evening. If left undisturbed for a season or two it is indestinguisable. I find conservation areas to be great for this. If you are storing any food stuffs remember to line the bucket with mylar and seal it so that the food smells don't attract enough attention from the wildlife that they get exhumed before you want them. Racoons and chipmunks and others might not be able to open the buckets and get at your stuff but if they take away enough dirt trying to do so then some biped might find and remove the bucket.

This approach is a mid-way between the limited usefulness of bugging out to an unprepared friend / relative / neighbor (who will help you utilize your meager supplies and then wonder why you are overstaying your welcome after the first few days) and having a fully stocked retreat in the hills. In this case the fully stocked retreat in the hills may be a corner of a conservation park and a cammo tent covered with debris set on top of the freshly opened geo cache. Not luxury accomodations but better than being stuck in the middle of the riots defending you freshly storm destroyed castle with the last few shells in your shot gun while you are waiting for the Nat'l Guard to clear enough debris from the road to get the APC into you neighborhood.