There are countless, countless examples where controlling a resource by locking people into the state you want them to stay in didn’t work. DVD encryption, DRMs, “regions”, etc., etc.
I thought the lesson had been learned, but I discovered yesterday, when I tried to upgrade an Acer desktop computer (E500) at a friend’s home from 1 gigbayte of RAM to 2 gigabytes. The motherboard supports that, but Acer locked it into supporting only 1 gigabyte. They probably hope that you’ll buy another computer instead of upgrading this one, and they’ll earn more money. Of course, I can probably find a way to flash some ROM in there to get rid if the limitation, but I just don’t have time to spend a day figuring that out. Sure, I’ll buy another desktop computer (or my friend will, rather). But it won’t be from Acer. Actually, I’ll probably not buy hardware from them anymore.
Folks, that doesn’t work, quit it. Does. Not. Work.
Update from 2009.0809: A few days ago, Apple did the same thing by locking people out of the Google Voice application for iPhone. People will find ways to install it, or will move away from the iPhone. Once again, in the long term, locking will not work.