I don't know about the rest of the world, but in Vermont I carry a come-along and some rope and logging chain: when the snow finally goes, the mud is on its way. I have only needed it once for my own car (not counting steep-grade plow truck woes), but have pulled several others out of ditches...

For tools, I go lighter than a lot of you: a motley assortment of the sockets I've used on the car and 1/2" and 5/8 breaker bars, screwdrivers, scraps of copper wires, a hatchet, a hammer, a knife, two flashlights, lug nuts, and a piece of tarp for crawling under her on dirt roads

empty 1 gallon gas can, washer fluid, oil, brake fluid, steering fluid, lithium grease, belt dressing

spare plugs and wires, distributor cap, fuses

and a blanket, because you never know!