From MorphOS Library
MorphOS has limited support for multi-display setups. On the hardware side there's multi-head support for selected Radeon R3xx/R4xx cards and configurations, including PowerBook5,x and PowerMac G5 setups. It's also possible to use multiple separate graphics cards in certain setups.
On the software side, in users' perspective, multi-display setups rely on the screens concept, which is inherited from AmigaOS. Separate screens can be configured to be opened on separate displays/monitors. The Ambient desktop will always be on its own screen and it can't be stretched over several screens, it's displayed on one monitor only, but you can open other programs on other monitors quite freely and decide which program is displayed on which monitor.
There also isn't a system provided way to move the mouse pointer to another screen by moving it over the screen borders, but it must be done by cycling the screens just like when using multiple screens on a single monitor setup.