Hydravision gives you many options for spreading your windows out across several monitors.

ATi's counterpart to NVIDIA's nView is called Hydravision. This software manages your windows when the card is operated with two monitors. For example, you can specify the monitor in which an application or its window messages should appear. The window bar is expanded to include several buttons that permit you to maximize a window in both or in one monitor, with just one click. The software ships with all the cards except Gigabyte and HIS. It's hard to fathom why these two choose not to include the software, especially since they both include the DVI-to-VGA adapter you need for the multi-monitor display. Be that as it may, you can still download Hydravision from ATi, so even owners of these cards can use the multi-monitor feature.

You can make individual settings for each application.