If you are one of those folks who regularly ventures outside of the realm of cell phone coverage and are in need of a functional way to either summon help or let the wife know that you are OK then you might want to consider a Spot Satellite Messenger. Spot uses GPS to dermine your location and communications satellite system to transmit that information to your loved ones or in the event of emergency to dispatch help via a GEOS International 9-1-1 response center.
The Spot Messenger is not a full blown emergency beacon, but rather fills a niche for outdoorsmen and women who may venture into the wild alone or with a buddy and who have wondered what might happen should they become incapacitated etc. A unique function is that the device allows you to either alert family and friends (via email and text message) to your plight or alert the authorities via the 9-1-1 key and summon professional help. The difference being that you have the option of alerting the wife to summon your fishing buddies come find your lost hindquarters down in the gorge or, in real life or death situations, calling on professional rescuers (and additional $8 per year provides 100k of coverage for rescue costs so bring on the helicopters). Another nice and somewhat less ominous feature is that the device can be used as a tracker that reports your location to a sharable webpage every ten minutes thus documenting your fishing trip and proving to the wife that you were actually fishing. (Don't worry. The device has to have a clear view of the sky to function so it can't work hidden in your trunk or anything like that.)
My initial back yard testing of the device delivered an "I'm OK" message to the wife within about four minutes of my pressing the button. It sent my Father a "Send Help ASAP" message (pre-arranged so as not to test his cardiac function) in a comparable amount of time. Text messages to cell phones included Longitude and Latitude information for my location and the email messages contained a link to a google map showing my back yard. I considered the test a success.
Currently Spot is offering a rebate of up to $150 dollars, which essentially gets you the unit for free, when you purchase two years of check in and help service ($99 per year) along two years of tracking ($49 per year). There are lesser rebates for those who only purchase the help service. Since the only way to use the unit for more than an orange doorstop is to purchase the service, this makes for a pretty good deal overall. As with all rebates, breakage means profits, so read the directions carefully and be sure to follow them to the letter or you will end up with less of a deal than you thought you were getting. The Spot Satellite Messenger retails for around $149 and is available are many outdoor retailers. Check out http://www.findmespot.com/ for more information.
**as with all of our opinions, be sure to do research on your own before trusting your life to something you read here or anywhere. We don't want you blaming us if you go and get yourself busted up or worse.