I think the most fun I ever had driving was when I test drove a Mercedes S600 (V12!) in Las Vegas on a small test track set up with cones in an empty parking lot. Nothing to crash in to, I really let the sucker loose and pushed its anti-skid technology to the limit. The best part was that my then boss was in the back seat without his seatbelt on.
A close second was when I rented a Dodge Viper for Ken's bachelor party. I was the second driver on the rental agreement and it was a blast driving it the 40 miles back to the rental place. Especially when I left a cloud of smoke leaving the toll gate on the Dumbarton Bridge.
