A German firm called 'Style Your Garage' creates posters for garage doors that make it look as if your garage is where all the action is. Made for up-and-over garage doors common in Europe, they mount with Velcro and can be adapted to fit sectional garage doors.
If you've got a two-car garage, no worries they can make posters that span both doors. Prices range from 199 euros to 399 euros for the double door, and the company can also turn a photo of yours into a garage poster, but you'll want to be careful with this, not everything can be blown up to 6 feet without looking weird.
What a great idea to freak out the neighbours. A police car would be a great deterrent for burglars!