FYI - at the Sensors Expo 2013, Colorado Microdevices and their RadioBlocks got 2nd place in the IPSO Alliance challenge for their Raspberry Pi-based asset tracking system:
Assest Management with Raspberry Pi and RadioBlocks
http://www.ipso-alliance.org/challenge2013/ipso-challenge-2013-interviews/cmd-asset-management
You can view all the winners here:
http://www.ipso-alliance.org/challenge2013/ipso-challenge-2013-interviews
The IPSO Alliance promotes the use of IP in low-power wireless networks like 6LoWPAN
BTW, here's my photos and videos of the Sensors Expo.
Cheers,
Drew