Not sure if anyone said it yet:
"Error! No keyboard present. Press ENTER to continue"
Any program I make contains random numbers. There is a good reason for this. If a user were to ever email me, I could look for the error code, and find it again.
Eg:
23849320591 Fallback error
Returning you to the last point
(subprograms inside a program might end early due to a programmer error or user error, and could cause the sub program to "fall back" ... anyways, since users dont seem to be smart about providing what they did before the error occurred, they might jot down the number..)