I know a member here had a $2 reversible royal hit for over 600k, the link here shows 1996 WSOP champion Huck Seed hit a $100 progressive for $670,000. The game was 100.65% at the time or $1300 per hour EV at 400 hands an hour. Likely worth about 1k more due to meter movement.
http://lockerz.com/s/126049089
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