RatherBeFlying,
A chap I once sailed with had a rather useful little 'Swiss Army Knife'. Whole thing about 3" long when folded, but the blade was a VERY sharp, serrated (like a steak knife) and lockable. Manually opened out (so not a flick-knife), but then needed a little slider moved to retract it. Where did he buy it? GVA air-side. It also had a combined shackle-key-&-knot-picker with a sharp point. Anyway - got it through there, plus other ports. It was loads sturdier and nastier than any box-cutter I've ever seen.
I personally haven't been through ZRH or GVA in a while, but my recollection is that such items were on sale air-side well after 11 September.