Cursorcerer allows you to hide the cursor at any time by use of a global hotkey. It can also autohide an idle cursor and bring it back as soon as you move the mouse.

Useful for hiding the cursor when using the control-scrollwheel zoom trick to make videos and flash content full screen.

To install, just double click on the prefpane. Hit control-option-k to zap and unzap the cursor. If you want to uninstall, go to ~/Library/PreferencePanes/ and trash Cursorcerer.