Cooking (proper food not junk), growing your own food,
personal finances, how to manage emotions, carpentry, welding, how to enjoy time by your own, languages (the more the better), how to do basic fixing of appliances (see RepairCaffe), learn the joy of not to stop learning, sleeping habits, health habits, be conscious what you want at work to be happy (depressed Manager or happy technician)...
To be continued... nice thread!