I also cache alone and often carry a can of bear spray and wear snake gaiters. Even though I may only be a few miles from civilization, Black bears and rattlesnakes are real problems around here. When I'm alone on the trail the additional bulk is truly minimal when compared to the defense they offer if I stumble into a problem. I've encountered both of these creatures several times but -- thankfully -- I've never had to rely on either the spray or the gaiters. I got the gaiters from Cablea's 20+ years ago.
If I go somewhere without good cell coverage I also take an frs/gmrs radio and leave a note in the corner of my windshield saying what channel I'm on. I use radios powered by AA batteries so my spare gps batteries also work in the walkie-talkies.
