There's a gadget you might like...
Modern cell phone jammers now operates on 3 bands including GSM. It costs a few dozens of euros in europe and doesn't look bigger than a regular cell phone, just an antenna and a button for a simple model. It won't ease the situation here, but at least you will have a good laugh when you see those
yelling in their cell wondering what's going on. Used in continuous mode, it will provide a quite large and safe enveloppe around your car but you will be jammed as well... Bikers in France use it on highways and city streets, any bike shop in Paris will sell it to you...
Even easier if you fly to the UK, it's legal to own there.
