Look through this and you find out about FCLAS.
http://www.rdecom.army.mil/rdemagazine/200501/itf_soldier.html
Thanks.
Off topic? but fascinating & I thought you might be interested Ping-
Speaking of fascinating, did you know that early this morning it was:
01:02:03 04/05/06
This has a description of the system along with illustrations showing how it works. Cool stuff.