I don't have the patience to sit there in the theater and wait. I just happen to come accross the two mentioned above on cable, and I didn't know how common it was.
I guess Cannonball run was the first movie I sat through the credits for the out-takes, but those weren't additional scenes. Also, I just heard the latest Pirates of the Carribean has one too. I'll have to check out the Transformers one when it comes out on cable.
"The problem with doing nothing is you never know when your finished."