Frontal Angle of Impact---angled up so it goes under other car, with strudy enough roll cage to hold up other car/truck.
BumperGuard--use car leaf springs around aoutside 1-2 ft away from car to absorb, then release impact--springy, so impact doesn't hit driver all at once--will bounce the car off, rather than crumple zones or sheer mass.
Roll Cage---build full roll cage into body.