For my birthday, my sister gave me 5lbs of orange Silly Putty. What do you do with it? What *don't* you do with it?
I mean, 5lbs of a somewhat oozy blob of plastic clay is impressive by itself, granted. But the applications to which it can be put are endless in number. You can hang it from the ceiling and watch its progress towards the floor. You can bounce it (imagine a 5lb shot put bouncing around like a super ball). You can even *wear* it for crying out loud.