In all seriousness, this has been done to death. Maybe against a first generation one-trick-pony MMA fighter he'd have a very solid chance. However, even against the second generation cross-training MMA fighters, he'd be pwned. Its a no contest comparing him to the third generation total MMA fighhters.
Moral: Bruce Lee was probably born too early for his skills to really be showcased and looked at intelligently, but not by much. If he'd been born 10-20 years later. There's little doubt Bruce Lee would have fought at UFC 1. And maybe even won. But today, he'd be lucky to make it out of the first round.
Sig courtesy of that photo-matic magician limba
I went out the way that I fight. I went out on my shield. That’s it. Done. --Chuck Liddell
My goal is to end my opponent --Carlos Condit