The main prank that we play with props is for people's birthdays. The special effects people will put a little explosive in the cake so it blows up in their face - that's always fun to play on a guest star, or one of the trainees or someone who's new.
Training should not be confined to trainees. It should be a continuous process, and should include the entire professional staff of the agency. The more our people learn, the more useful they can be to our clients.