I got a few in one of the rolls I bought, I stuck them in my safe with the two error twenty dollar bills I have. I don't really have any reason to sell either, so I'll just hang onto them.
By the way, both bills are missing the green seal and serial numbers. I wonder what they are worth?
I used to be really into coin collecting when I was younger, but it just got to be too expensive. Now I just collect the odd coins I get in pocket change, new coins the mint puts out, and the occasional gold eagle (my favorite coin). I've been wanting to pick up a platinum eagle proof set, since I don't have any platinum coins, but the price keeps scaring me away.