Not an intentional prank but still had the communal shoulders shaking...
Pompous oaf of a boss was due to exchange contracts on a house. He had to go to a meeting but would be back within 30 minutes. If his mobile were to ring, we were to take whatever ultra-important message came down the...
Worked with a girl called Alex Davison once. We all had our names on our desks on these little pegboard things with white letters. Every day when she came back from lunch, without saying a word, she'd just sigh, roll her eyes and rearrange the letters for I DO ANAL SEX back into the correct order.