"Please choose the items to install. ATI Catalyst drivers: (required, 15M) ATI Catalyst control panel (optional, 9M)"
So, basically, my custom choices consist of "do I want to install just the drivers and save about one cent of hard drive space" and "do I want to install everything that I just downloaded and actually be able to control my video card".
Why do they even bother having a custom option? :P