Larry Allen- most dominant OL I've seen play.
I started watching football when John Hannah was playing or the Pats but don't remember much about him. I know he was really good too though. That said, Hannah never could have had an all pro season at LT like Allen did.
Just amazing combination of power, athletic ability and nastiness, in addition to be technically sound.
Too bad Big E had that stupid night out where he ruined his knee, otherwise there's a decent chance he'd have been in HOF as well.