Out of all of the great men i've been reading the works of over the past 6-7 years, Terence McKenna is by far the most interesting and far-out. I think he was way, WAY head of his time and his work may not become mainstream until around 2040, or whenever Singularity-type events begin to happen.
This is a 3 and a half hour, very well-compiled video of Terence McKenna talks and lectures. Very entertaining and educational (and funny) guy. Would have been cool to meet him.