I know a couple of people who got carjacked.
One rather spectacular one. In Belgium, a couple travelling in an Audi S4 between 90 and 100 mph, were followed on an empty motorway. After a while the car nudged them from behind at that speed. Then it pulled along side an one occupant pointed a gun at them beckoning them to pull over - which they did. The couple were left stranded on the side of the motorway with nothing.
They waved down the next passing truck to get help. Anyway, it was all well planned, but I cannot be bothered to write anymore now, so if you wanna know, say so. Explain later.

Not much you can do when faced with a gun pointed at you , wonder if your insurance would pay up if that happened 
Not a lot.
Car had a tracker. It lay low a while in Lille, France. Police suspected it was being kept out of the way and not used so the gang could work out if it was being tracked - and so to use it in a bigger job as a getaway car - bank or something.
Anyway, the plan that got the car was this.
- Car pulls into services for fuel not far out of Calais after leaving ferry
- Driver wants to pay by card.
- Card reading machine had a "fault". Needed restarting - this is when the car was "checked out"
- Driver paid on got on way.
- In the meantime, the gang had got themselves into position.
- Gang was 3 cars.
- Two cars drove side by side on the 2 lane motorway at a slow speed to hold up all other traffic.
- Car 3 (Audi A6) went on and did the deed.
Anyway car was eventually recovered after Police had been "watching" it for some weeks. Caught some of the gang too, apparently.