I just went and bought a new screen for my PowerBook G4 today!
Now all I have to do is wait 3-4 days. Finally, I'll be able to use it as a laptop, except I don't have a battery…
What I do is use a flathead screwdriver on the tab, and use it to get some leverage. Even then, it takes a LOT of force, and you can end up breaking the tab. :-/