My best so far is 38 rides on Hulk at IoA - that was during the 2-3 month long passholder previews prior to the park grand opening to the general public. And I also had to run the que each time, needless to say I was doing that all day.
The best I've ever seen was my friend Kevin, over 100 rides on Kraken at SWF during their media preview day - he just rode over and over and over from about 8am until past 6pm, and the SW staff just kept letting him ride and ride. I got about 25 rides on Kraken that morning, got tired and went back to work.
Have Fun!
George