I’ve enjoyed regularly changing up my GTK and Metacity themes, but until recently I have never switched to a new cursor set. There are many high-quality cursor themes available, and they are easy to install in GNOME.
There are some packages containing cursor themes in the Ubuntu repository: comixcursors, crystalcursors, and oxygen-cursor-theme (click any of the links to install).
Beyond the repository, GNOME-Look.org offers a wide selection in the X11 mouse themes section.
Cursors you download yourself should be in an archive format, but you don’t need
to extract them. Open Appearance Preferences
System->Preferences->Appearance), and select the
Theme tab. Drag and drop
the file you downloaded into the theme browser area to install it.
To manage your installed themes or switch to a new one you installed from the
Customize and select the
You should see your new cursor theme immediately, but to completely apply it to all applications, you need to log out and back in.