Saw this on CU:
http://www.ebay.com/itm/351758390342...%3AMEBIDX%3AIT
The point was made the last auction for a PSA 8 ended around 4500. I checked the pop report, there are around 180 8s.
Also, just for fun I did an eBay search and found 4SC sold one just this month for $6,499.99. I was really hoping the cert was the same, but it wasn't. If I tried something like that (buy for 6.5 sell for 17.5), I'm sure I'd lose money on it