I just bought the Call of Duty 4: Modern Warfare 2 on Mac OS X but need to know what I need to get in order to play multiplayer. I know that Steam is used to run multiplayer on PC, but what should I do for my iMac since Steam is a Windows only software? I have a few options.....download Windows in BootCamp, which I am trying not to do; could download CrossOver or something like Crossover but I read that it makes my computer slower (even though I have 980 GB of free space left). What should I do?