This is moving move towards a distraction and something you probably shouldn't do. However it's hilarious when you pull it off, so... Cloak their IP and a 10 m

This is moving move towards a distraction and something you probably shouldn't do. However it's hilarious when you pull it off, so... Cloak their IP and a 10 mile radius. Show them a new homepage saying you've got fabulous new features in the works. Think up a series of completely useless features that would drive people away, but frame them as plausible. Back it up with facts and figures from "in-depth" user studies you've done. Then watch them try and beat you to develop the features. It worked for me in the past.