Hack for SMS or Tweets over GPS (iridium, etc)

Devices that allow for SMS over GPS (Iridium network I think) - such as the FindMeSpot (http://findmespot.net.au/SPOT-Satellite.html) - are getting quite cheap - around $200, and their data services are about $149 per year. I want to send my sensor data over this type of connection (GPS) where no cell phone signals are available. So I was wondering if:

  • Has anyone hacked a Spot GPS messenger to work with Arduino?
  • Has anyone used an alternative solution to send data over GPS?

Thanks.

The SPoT tracker uses the Globalstar cluster of satellites. You could get the programmer's reference manual for their transmitter which is probably built into the SPoT tracker. http://www.globalstar.com/en/docs/stx2/STX2%20Sell%20Sheet_FIN.pdf