The
trojan boot is an idea whose time has come. Everyone is familiar with the process of booting a
car: When you're illegally parked, the
police will often attach a very large and heavy chunk of metal to one of the
tires. Since you've got this big metal thing attached to your car, you can't drive off. So you've got to go pay the ticket or whatever.
The trojan boot makes use of the fact that a car with a boot on a tire looks like the police booted it. All you need is a boot and the key to it. Go park your car somewhere nice and illegal. Open up the trunk and get your boot out. Boot your car and go about your business. When you get back from doing whatever, unlock the boot and you're free to go.
Since your car is already booted, the cops aren't going to go to the trouble of booting it again. That's the trojan part of it. Now congratulate yourself: you've just avoided the long arm of the law once again.