BlackBerry enterprise resilience
Research in Motion, makers of BlackBerry, are a spectacularly successful company. They had a great idea and made it work, when you would have put odds on Nokia or Sony beating them.
However the BlackBerry Enterprise Server software that makes BlackBerries work for businesses is a spectacularly bad piece of software. This piece is intended not as a criticism of RIM, but as a comment on the business of creating enterprise software.