Unsurprisingly, Gary Gygax's death has spawned a number of memorials in the webcomics world. Dork Tower has gone to a grey-and-black background. Mike of Something Positive has gone into (predictable) catatonia. And a critical miss on Arthur, King of Space and Time leads to a "Who's Gary Gygax?" result.
I think the best tribute, though, is at Rich Burlew's The Order of the Stick, where a stick-figure Gygax meets up with the (currently deceased) Roy Greenhilt:
"Those of us lucky enough to spend their time kicking down doors and slaying dragons for a living owe you an extra debt."