Are you good at typewriting and always hit the right keys? Then you don't need iJect. If you often miss the target key on the keyboard, you will need the backspace key frequently. However, if you miss this one on (for instance) the new iBook, it is very likely that you hit F12 and the CDROM tray will open. There are two solutions for this problem: Either you practice typewriting or you install iJect.
What's new in this version:
1.2 should now work on all computers which run Mac OS X 10.1, not just the new iBook. Disables F12 completely, you can't re-assign it to any other function.