The Light Middleweight division from 10 years ago for not fighting each other. David Barnes and Brett Flournoy, I don't have a clue why these two didn't achieve more. Ricky Burns for having boring fights against no hopers since beating Martinez.
Herol Bomber Graham for me,always looked world champ material,never shirked the fitness side(even now at his age he looks in hos 20's).
Having seen Brett Flournoy in prizefighter I really liked his skills had a lovely shoulder roll and was slick and technical in a style we rarely see coming from these shores. I thought he could have really made an impact in the domestic welterweight division because he was fighting above his weight in prizefighter. Sadly he hasn't fought since....
A few, it's hard to pick one: Calzaghe, for the reasons mentioned earlier. Hatton, again for the Pacquiao stuff and Hamed...yet again for the stuff mentioned earlier. Only one outside the UK would be (I know, I saw the thread title **** off I'm mentioning it anyway) Edwin Valero for obvious reasons.
Hatton. Even if he knew he had peaked too early before the manny fight, why didnt he try and box a little bit? At least he would have made it a fight. He just went out there and played right into his hands, swinging wildly, he was asking to be sparked.