I've been thinking on this for a few hours, how Gygax influenced aspects of the world.
It could be easily said that he started modern gaming; Chainmail & D&D are in the background of every role playing game; some of the first Computer games were D&D based, which influenced not only all following computer & video games, but also the demand for personal computers in the first place. I've lost track of how many people I know got involved in programming due to D&D.
Some of the very earliest traffic on arpanet, which evolved into the internet, was Fantasy Role Playing and adventure gaming.
How many people signed up for AOL or Compuserve to play online RPG's obviously based on D&D? how much did that effect the development of both the internet and modern MMORPG's?
AND, while Fantasy art was around before Gary, How much would there have been without the D&D spawned books, magazines, games, movies, etc? Throw that in with his influence on personal Computers & the Internet, and you have a argument that Mr. Gygax is directly responsible for Renderosity.
Regardless, I know that I could cite Mr. Gygax as the reason I have 3 wonderful kids; I met their mom in a Gaming store.