Autocrossing is fun! I used to run Autocross about three years ago when I had my 98 BMW M3 Sedan and 98 M Roadster. These cars where fun to carve through the cones with but the class they where in had very close competition.
Usually wound up around the middle of the pack considering that I was running with pricier exotics like Vipers, Lotuses, Porshe and the like. It can be cheap and fun in comparision to track racing.