Working in IT I have dozens of monitors on my desk at any time. Smooth scrolling seems to be a pretty common complaint. I don't play a lot of games that rely on smooth scrolling (more of an RPG guy, myself), but I would recommend looking for one with a fast refresh, or an ultrasharp model, such as a Dell P-series (Professional) or U-series Ultrasharp model. Preferably one with a native 4:3 or similar aspect ratio (such as 17", 19", and 20" screens).
Of course at home my A500 is hooked up to a 55" TV, so I don't always follow my own advice.
