An in house knockout style gaming tournament could be a good idea it would obviously have to be done over a series of weekends so time difference wouldn't be an issue.
Games would have to be Old school Cheap and Easy to obtain for those that may not have them and guaranteed to run no matter the system someone is using. And obviously without an in game level system so that everyone is on equal footing.
we could have categories like RTS, Fps, Fighting and maybe a sports game of some sort Car Racing springs to mind?
Games like-
RTS: Warcraft 3 TFT, Command & Conquer, Red Alert, Age of Empires II.
FTS: Fear, older Battlefield games, older call of duty, older Medal of Honor, Counter Strike.
Sports: Need for Speed- Underground 1, Need for Speed- Underground 2, Need for Speed- Most Wanted.
Fighting: Mortal Kombat: Komplete Edition (it's only like $10 on steam or something)
One game per category to be decided by OC3D, Have epic prizes a top tier component of some sort for first in each category or something even cooler like an OC3D one of a kind item like a Custom OC3D case? (wouldn't be to hard if you got corsair involved for prizes), then Lesser yet still awesome prizes for 2nd, 3rd and 4th in each category.
Prizes would have to be pretty cool to attract alot of entries, And also make the time invested by the players worth it.