Biggest thrill for me was on an AC DC-9 about 18 years ago. I was the winner of an Aeroplan contest as they picked my seat number (this was mid-flight). I was told to go to the cockpit to claim my prize. While there, I mentioned to the pilot that I had never been in the cockpit before. He told me that when they were about 20 minutes from landing, to come up and I could sit in the jumpseat. So I had a first-person view all the way to touching down on the runway. By far my greatest flying experience!