It's clearly just a matter of time before DAVE-Fest becomes recognized as an official National Holiday, and then certainly an even shorter period of time before it's an Internationally Recognized Holiday (it'll probably be a bit longer before it becomes a Bank Holiday in England, but that's those wacky Brits for you...).
Anyway, DAVE-Fest is a tradition dating way back to June of 1995 and involves the extended Festing of All Things DAVE, or at the very least, an extended celebration of DAVE's birthday.
To really understand more of the Zen that is DAVE-Fest, your best bet is to read the Official DAVE-Fest Reports: