Unexpected problems with ordering 250 pounds of Silly Putty to give away to friends. In particular:

The problem was that once together, Silly Putty doesn't like to come apart, and none of us had any idea of how to deal with this effect. We tried everything: very strong people (didn't work), scissors (stabbing worked, slicing didn't), 28-gauge steel wire (broke), 22-gauge steel wire (broke), 16-gauge steel wire (too thick), and twisting and breaking (worked well for "smaller" pieces -- under five pounds, that is.)

(Via Boing Boing.)