The new swappable-bit tools come in two forms: a fixed T-handle with swappable bits, and a set of two Sticks that can be formed into a T-handle, also with swappable bits. The appeal for bicyclists and motorcyclists is easy to see, but I think these would make a great addition to a basic emergency kit (or minimalist toolbox) for any type of vehicle. 

These Modular, Bit-Swapping Wrenches Are Brilliant