Fake Parking Tickets
The ticket is worded clearly enough to allow someone reading it after discovering it to know that they have been pulled a joke on. It is written well enough to sound almost legal but fake enough to be able to pull it off. The bright orange color will allow for the person who is receiving the ticket to be able to see it from a distance. They will realize once they notice they have a parking ticket that the sinking feeling in their gut is from the fact that they might have done something wrong to validate as to why they are receiving a parking ticket in the first place.
With all the new shows on about parking ticket wars and the hilarious way that most people do not believe that they did anything wrong in order to even validate the ticket makes it that much funnier to pull on someone. To make matters even worse, maybe to pull the joke off even better, you could hire someone to show up looking like a police officer to write the ticket out and place it on the windshield. It would be funny to make sure that the person you are pranking is standing by when the ticket is placed on the vehicle.