Jim...
I am glad you are in the "know" about the RFID Readers, Spychip and Digital Angel.  How about reading up on M.M.E.A.  Pull up on the search engine and enjoy the read.  This tech has very far reaching abilities.  Might I add that watching the movie STEALTH will give you all a thrill in technology not thought about.  It includes the tech on RFID, Biometric, and GPS that can see your eyes from 39,000 ft and further.
 
Go rent the DVD and see what is now rather than future.
 
Patty Hayes