(F)utilies

Saving potential: ~ $100-200 monthly, $1200-2400 a year

Time investment: None

Useful for: Everyone not homeless

Americans are too damn comfortable in their houses. This is possible because we cool down or heat up our places with the AC running all the time. When you live in a fairly big house (typically with bad insulation) that's a lot of air to process. Bigger also means more surface for the cool or heat to dissipate from.

"B-b-but I need that!" you whine. WRONG! Your body is built to survive in the most adverse

environments; you just forgot about it living a modern life. Your ancestors had none of that and were doing just fine. Of course they learned how to deal with a little discomfort and turn it into hardiness. 

Here's the catch: You don’t even need to go to the extremes. Just lower your thermostat to 62 degrees in winter and 78 in summer and you'll save hundreds of dollars. The difference is  negligible. Obviously you'll complement this with appropriate clothing. Ditch the shorts in winter (you idiot), wear warm socks, and a wool sweater instead. Wear sunglasses in summer...

Also, stop blasting the AC on full in your car. It burns quite a lot of fuel and makes walking (healthy and cheap) outside of the rolling fridge much harder to bear by comparison.

In addition to the savings your body will become more hardened and you will accommodate to living with less. Not being dependent on certain equipment with limited (or costly) availability is always a good thing.

Top that off with cold showers for a stronger immune system, increased alertness, and a benefit in badassery.