From a thread on Facepunch (http://bit.ly/TPnXHT):
Ok so I think I figured out the "alienware" mode in the options menu. I'm guessing that it has to do with the alienware "AlienFx" stuff. I guess it makes the keyboard or whatever the hell it lights up light up in sync with the music or how many people you kill or something. I'm just taking a guess from the Alieninmiami.dll in the game folder.