More than just the d100 he was a pioneer of being very exacting when it came to making polyhedral dice. See http://www.1000d4.com/2013/02/14/how-true-are-your-d20s/

> More than just the d100 he was a pioneer of being very exacting when it came to making polyhedral dice.

Absolutely, but i couldn't fit all of that into the subject line ;) and he's best known for the d100. Many of us remember the articles and ads from the 1980s describing the effort he put into that particular die.