If the SHTF, antibiotics will be scarce, which means many people could die from minor infections. Learn to make your own antibiotics. - I'm allergic to penicillin but my children aren't so this is definitely going in my book
Make your own fire starters with items you already have in your house. These were free and easy to make and burned for 30 minutes. Fire starters are handy to keep around for campfires, bonfires, and any occasion where you need to quickly start a fire.