I've also signed up as organ donor. I won't need it when I'm dead.
I really believe that if I should expect to receive an organ if needed, then I also should be willing to offer mine organs.
Here in DK we also need to sign up. I think it would be better if we all was donor as standard, and then we needed to sign off, if we didn't want to give organs.
I might go as far as saying; if you won't give, you can't receive. That would solve the long waiting lists.