Just got an email in my inbox alerting me to a Crysis Wars trail period coming around. Those of you familiar with Steams weekends these work in much the same way. Sign up at MyCrysis , Then when 19th comes around you have 10 days to hop in and play Crysis Wars, the multiplayer component of Crysis, for free.
If you’ve yet to play Crysis or its MP modes then I strongly recommend hopping on. Cryisis has a fair range of big maps, and the nano suit helps spice things up with almost an on the fly class change. This is running on the optimized Warhead version of the CryEngine, so you don’t even need a supercomputer to play this. And as an added bonus, once 29th hits you can still play this over LAN. Also these free trials tend to crop up fairly often, so you should be able to get a fiar bit of use out the download.
Instructions and FAQ are in the link, and the Steam group (in the Links ->) will most likely be running an event.