This thread reminds me of a rather well known story at wall street.

Day 1, new Associate #1 walks in with a Gucci belt, with the big G sign.
Partner #1 says to him: 'I didnt know Guess made belts?'
Associate #1: 'Its Gucci'

This guy got fired not long afterwards for 'not getting things'.

Another thing people used to do is if new Analysts left their computers unlocked, we would go in and change the homepage to www.rolex.com or something similar.