I have ten "intentional" duplicates (both the mistake and the correction of a sculpture; i.e., Split Rock, Michigan and Split Rock, Minnesota) and 80-90 LEs that I hope to sell one day. I had most of the pieces I won on an eBay auction, but I wanted the auction pieces because their numbers were lower than what I had. I hoped I'd be able to sell those that I had, but the market went south (to the Pole!), and I'm waiting for it to come back.

I'm always on the hunt for both mistakes and low numbers, so duplicates and sometimes triplicates are not unusual.