My laboratory equipment and extensive supply of reagents, microscope, seeds of Papaver somniferum, Cannabis sativa seed+ a nice big fat sack of both resin, skunk and oil, plenty other various meds. Scientific textbooks, computer. Non-perishable food, gas mask, a handgun and a good supply of medical kit, a swiss army knife plus a strong single-bladed sturdy lock-knife. Rolling baccy+liquorice papers, as I imagine 100yr+ from now fags will be either extortionate in price beyond even what the situation is now, and become luxury goods.
Secure computer hardware with a clean installation+selection of security tools.