Here's one For Sale ! http://cgi.ebay.com/TOP-POP-1990-No...11?pt=Coins_US_Individual&hash=item256523b33b
The copper has slowly worn off. As you know pennies after 1982 are copper plated zinc, so sometimes the copper will wear off, this looks like it was used heavily in a vending machine. Proofs do not have rims like this, they are the same as any penny.
Browncow, that post was from over 6 years ago, and that member hasn't been on since 2014. Welcome! Jim