Best combat sim that will run on a laptop
I have a Core 2 laptop with X3100 graphics accelerator, in order words, all top of the range 3D games are out for me including things like OFDR. Those that will work like the old Swat 3 is no where comparable in depth and realism to ARMA. ARMA is definitely the best combat sim that I have ever played that actually runs on my laptop on low settings. Even on low settings, the environment looks great and the characters behave in a realistic manner.
Combat is realistically done with realistic sounds and nothing fanciful. Its really a tactical sim where taking the correct moves on the field is much more important than being a crack Doom style shooter.