There aren't many single special days or "holidays" in this gaming hobby of ours -- convention season, Free RPG Day, new product day each week at the local store -- but there is one event that began fairly recently. GM's Day started out through postings on ENWorld and soon spread throughout the online gaming community. The date of GM's Day coalesced around the anniversary of Gary Gygax's passing.
Be sure to check out some of the sales at DriveThruRPG/RPGNow this weekend:
And if you're not a GM, what better time to start than now?