I am a big fan of sattelite messengers and the SPOT Gen3 is on sale at Cabelas for $75.
I run a DeLorme InReach on the SAR team and an ACR ResQLink while hunting, but have handled the SPOT. At only 4 ounces and $13 subscription fee per month, it is some of the best survival insurance out there, when paired with a trip plan.
Thank You, Purchase one!