Below is a list of games and files you must have installed and updated before the event (if you don't have a particular game and don't wish to get it for the event then you can spectate/do something while those games are being played). A 'synchronise' time will be posted to try and ensure everyone has the same versions of steam games at the event.
PR:BF2 v0.97 (tested online prior to attending the event)
ArmA 2 and Operation Arrowhead with PR:ArmA 2 installed and updated
Red Orchestra 2 (it will have some large maps with 64 player support so it should be entertaining!)
Other games that might be played (some perhaps when people start calling it a night on Saturday and the numbers drop):
Unreal Tournament (the original)
Left 4 Dead 2
Battlefield Pirates 2 v2.1, (or v2.5 if released in time - check the PR CON Forums on realitymod.com a few days before you leave)
Counterstrike (as per request)
(All games, unless linked otherwise, are available on Steam)
A zip file including all the relevent files for the lan such as custom maps etc with instructions on how to install - this will be posted/pmed for people to download and install approximately 4 days before the event and will be available at the location as a share.