The logitech SpaceMouse and SpaceBall are alternatives to dials that are supported by O on SGIs running IRIX 6.2 or above.
In order to run them, you need to install the xdriver demon that comes on a CD when you buy the device (or can be downloaded from http://www.logicad3d.com/software/newsoft-archive.html). Once this program is installed (in /usr/bin/xdriver), it can be configured to start whenever the system is rebooted, or it can be run by individual users. If they have /usr/bin in their paths, they can just type 'xdriver &' to set it going in the background. The xdriver demon interface has many settings that can be altered. Here you must set 'Application', to 'X-Windows version 2.0/3.0'. The demon detects whether you have a SpaceMouse or a SpaceBall plugged in, and calibrates itself appropriately.