I'm with most of you guys... most Aston Martins are gorgeous. V12 Vantage is stunning. 458 Italia as well. I suppose for $150 you'd have to get a used V8 Vantage or such.
We are biased, although at its price I really do think the M3 is the best looking car. It's simple, elegant, classic yet modern, and aggressive all at the same time.