My old Gerber LST-2 knife held up well. Now in my pack to use as a fire starter with the magnesium stick. Its light weight, thin and you wont really notice it.
Now I carry a Swiss Army One Handed Trekker which is the same model as the current Swiss issue less the green hand grip with the rubber pads. It comes in handy quite often. Just in the last 3 days, I had to open pop and beer bottles with the opener at a local celebration (Europe still uses the crimped not screwed type on glass Coke and beer bottles), use the screw driver to take out the anti-thief plastic brackets from a kids toy, and a cut a few more things.
I am told carrying a "Swiss pocket knife" (Elvetiko Soya (sp?)) is ok in Greece just not carrying of regular knives, never did ask a cop though. But I have not had a problem in the 8 weeks now.
Dimitri