The magnetic England car flag is a great idea to stick on your car whenever you feel like flying the flag. You could leave it there all the time or, being magnetic, it will stick to anything metal, so could be used in all sorts of places too. 

The magnetic England car flag is pliable but firmly made, and is heart shaped with a diameter of approx. 8" x 7".  It has a red George Cross and 'England' emblazened across it in black on white.  On your car, it could look as if you've gone to the expense of sign-writing, but it can be easily removed whenever you feel like it.  So, the best of both worlds!