Revenge of the developer.
After our project consultants aren't good at planning projects I started my revenge. They will get soon a heart attack or paranoia...
Every time I need something from them (cause they missed it in the specs) and see them at the end of the floor. I stealth in their room and stand behind their door. When they are sitting, the door is closing mystically and I step to them. The faces are hilarious. That's my way to teach them to write better Specs :)