The "Trades": Carpentry, Plumbing, Electrical. NOT just as a job... most Americans own houses... knowing these skills can save you tens of thousands, and potentially add massive value to your property. Its a great fallback in case you lose your job.

Contract Negotiation/ Drafting. In the future much of our drafting work will be normal people using templates from the internet. Knowing the basics of drafting will save you a bunch of money and keep your risk levels down.

A Foreign Language. If you are based in the US your top choices should be Chinese (Mandarin , Cantonese) or Spanish.

Bartending/ Cooking The single fastest way to get decent income in case you lose your full time employment. PLUS I would argue culinary skills are valuable in business.