If your 'out of range' is typically the same place (eg. your home), you could have Internet access there and get a Chumby (http://www.chumby.com/). You could both have it load either a service you maintain (eg. Nagios) or a service like pingdom, OR you could whip up a little program (the Chumby is very hackable) that sets off an alarm based on a Nagios/pingdom status.
Another option along somewhat similar lines would be one of the femtocell or 'hotspot at home' solutions from your wireless carrier. This would kill two birds with one stone.
If you tend to be moving around when you are out of range, then perhaps what you should first investigate is paying for remote hands or setting up automatic actions (eg. system or service cycling) in Nagios or similar.
If none of these work for you, then maybe your Satellite pager idea is the answer.