Check this bad boy out - TWO-WAY text messaging and position updating through the Iridium sat-phone network.

http://blog.delorme.com/2011/06/03/d...communication/

This might actually convince me to get an Android phone, since my wife has expressed an interest in having me get a SPOT. Of course, if they release an iOS app (like they seem to be mulling) that works with the iPod Touch, then I'm already set up for such a device.