[ZachS]

I would probably buy a cheap, unsigned HOF postcard on ebay and play around with it. That label was made by one of those older punch-type label makers (the kind where you turn the wheel to a letter and pull the trigger... I have one in my desk). I would stick some labels to the test PC and see what happens during removal.

From my experience with those older labels they're fairly easy to remove (especially as they get older) but sometimes they leave behind residue. Usually the adhesive on those isn't strong enough where it's going to rip off the paper when the label comes off... but like I said, it will probably leave behind some residue.

ETA - I would definitely try the heat gun/hair dryer first as recommended by the other posters.