500
These are the rules suggested in the film Zombieland as a way of survival.
What are cardio, double tap, beware of bathroom, seatbelts, cast iron skillet, travel light, get an awesome partner, bounty paper towels, bowling ball, don't be a hero, limber up, Ziploc bags, when in doubt know your way out, the buddy system, check the back seat, clean socks, hygiene, always have backup?