Interesting and useful discussion. I do agree with the "if you bring a ton of stuff, the thing that breaks will be the one thing you didn't bring" crowd. For long trips with my (much newer than most in this thread) car, I bring a couple of multi-tools (one that tends more toward screwdrivers and one that tends more toward knives). A couple of appropriately sized wrenches and a wide (lord help me) Torx array go a long way toward fixing some issues. A set of fuses, motor oil, a serpentine belt, and a good portable air compressor complete the list. I'll be honest, though: most of my issues have either been solved with the AAA card or quick help over the internet.