I'd second the Corrado (if you can find one for the price in decent shape)
I would also look into these cars:
Nissan 240SX -yes, everyone has one, but for good reason (they are cheap, handle well, and ideal for mods)
Honda Prelude (3rd or 4th gen.) -excellent cars that handle and perform well for the money (and very reliable)
Toyota MR2 -if you want a fun car that few people have (not as practical as the others though)
Mitsubishi Eclipse (1st or 2nd gen.) -very responsive to mods but also very hard to maintain (if you are willing to put in some work, this can be an excellent choice)