WAY!...I'd use a whip to keep them out of my office. WAY!....He called me a "Grumpy Old Coot" and WAY!....I liked it! In fact...I'm thinking of having a T-shirt made.....
You could set up a rule that no shoes were allowed in your office and get you one of those shock pads that are used to keep dogs away from a door. A couple of good shocks and they would probably give up and stop coming completely.