BMW Z4 = affordable, fun, best handling roadster and some say of all BMWs...about 40k or in a few months the new BMW M3, 400BHP, best handling all at around 60k...
A good "older" car is an Acura NSX if you can find one in good condition that was taken care of well, it's fringe super car and run 30-50k these days.
good midlife fix, you'll get over it and upgrade to a mercedes s55 so there are some quick fixes for ya