I just got back from doing aerobatic maneuvers in an AT-6G Texan out of Taylor Mun in Texas. It was a blast! After the first few minutes, I was doing rolls, Immelman's, cloverleaf's and a couple of others. I have a tape of it, and I'll post it on SimTV as soon as I get it onto digital format.
If anyone is interested in this type of flight, it's not TOO expensive (around $400 US) for a 30 minute aerobatic flight.
http://www.bluegrasswarbirds.com/