I had a large hole in a tire and had to walk my bicycle back over 5 miles. I now Cary a spare tube and small portable pump. I also switched my tires to one's with Kevlar banding.
Carrying a bicycle specific multi tool after trying to help someone on a trail.
Yeah punture resistant tires are a great thing! Also a spare quicklink can be handy if you break your chain.
Kitty litter after getting stuck on an icy Street.
When I used to have a full size rear wheel drive car I used to put a large bag of salt in the trunk to better distribute the weight. Anyone who has had the back kick out in the winter knows the feeling. I now won't consider buying a car without AWD or 4WD.
I really like those small foldable plastic traxion plates. Works really well in snow/ice and sand. In in my trunk year rond.
I never really had issues with the back kicking out. But I do always make sure i have proper tires for the conditions and drive slowly. I also think west europeans roads might be better cleared of snow and ice...
Rotating the tires every other oil change. If you have aluminum rims the tire can, (and did), seize to the hub. The emergency fix is to loosen the lug nuts and drive slowly a short distance. Rotating the tires frequently should stop this from happening.
Happens to steel rims too! The solution, put some proper anti-seize on the mating surface between the hub and rim. (do NOT put on the bolts). I change out the rims with tires twice a year from summer to winter and vise versa.