I can't tell whether this is a serious list. Replaceble battery sounds serious (I mean, I don't want one, but sure). GPS gizmo? Small camera? RAM?
Other contractors I know in the west coast just leave their cell phone in their car when they go on base. It just sounds like your friends are using the old "I have a security clearance" excuse to not have a cell phone, which, if its the case, more power to them. :)