Leatherman - Strap one to your belt and it's like having not-quite-the-right-tool-for-the-job on you at all times.
A multi-purpose tool favoured by many members of the British Army. These are routinely 'confiscated' (i.e. stolen) by RAF Movers and RAF Police because they allegedly constitute 'dangerous air cargo'.
This presupposes that despite having volunteered for military service, being carefully trained and vetted, and almost certainly being in possession of a fully functioning firearm, there is a risk that some soldier will attempt to hijack a military flight using a 3" blade. Yeah, right.
Oddly, for a good and useful piece of kit, the Leatherman is available from Man at QM as a 1098 item. For those stupid enough to try and get one the NSN is 5110-01-541-1453 - (Multi-tool Folding Leatherman).