heres my list...
GM: fiero/LT1
Honda: 84-87 CRX/ B-series
Nissan: 240sx/RB25det or 510/sr20det (not a fan of the rotary 510)
Ford: sierra cosworth or merkur XR4TI/302
Hyundai: excel/4G63
Toyota: IS300 or altezza/2jz
Lotus: elise/b-series
Volkswagen: beetle/chevy large block

BMW: 318ti/e46
thas all i can think of right now... what are your favorites?