For those interested in background of the microkernel (not the L4 runtime environment): Jochen Liedtke, On microkernel construction. http://elf.cs.pub.ro/soa/res/lectures/papers/lietdke-1.pdf

I'm happy if that is true, but guys: the first thing you think of is putting a potentially massive explosive on the back of a truck? Driven by humans? What could go wrong...

True, but we currently have gallons and gallons of highly flammable liquids hidden behind the cheapest #8 steel possible and something literally called a bumper, all exposed to whatever rust and rocks the nation's roads can throw at it. It's all about the level of risk.