Well, this is surprising! Crysis 3 Alpha codes are now open, with NVIDIA and EA have teamed up and are giving out 5,000 keys to the first 5,000 people who sign up to this page starting right now.
Once you've secured your key, you just have to enter it into Origin, and you'll have the game sit there until the pre-load is ready. The game is just an alpha copy, which means it is most likely buggy and no way a representation of the final version.
But, get in right now if you want to check out Crysis 3 before the rest!!