I have one big bag, affectionately known as my purse, that has all my hand tools. It's one heavy SOB but all my sockets are organized on strips, all my pliers are tucked into the side pockets, I know where everything is. Very rarely do I not have something I need. On the longer trips where I know I'll be hours away from a real road, I bring a five gallon bucket that has a few spare parts, a pickle fork, 2.5lb sledge, map torch, c-clamps, and some fluids. I also have another bag with my air tools and big sockets. 99% of the time I'm supplying the tools to others.