It’s cold outside. Really cold. So it’s no surprise that interest in cheaper, more sustainable ways to warm your home tends heat up this time of year.

Here are some unusual strategies for keeping homes warm — some of them you can even try at home.

Heat the person, not the house: Permaculture blogger Paul Wheaton says he has slashed heating bills by focusing on heating the person, not the house. He used several contraptions, including a heating mat to warm up dog beds, an incandescent heat lamp, a skirt wrapped around his desk and even a heated keyboard. This approach might struggle to get mainstream appeal. That said, the principle is utterly sound, and can also be deployed in less extreme forms.

From Jimmy Carter’s advocacy for wearing a sweater when it is cold to a push to make electric blankets cool again, we can all look for ways to keep ourselves warm — our houses don’t care if it gets a bit chilly. See a video of Wheaton’s methods here:

Warming with compost: When it’s made right, compost creates heat. And that heat can be put to good use. Search YouTube for “compost” and “heat,” and you’ll find plenty of videos exploring compost-heated showers and greenhouses. But permaculture expert Chris Towerton has been experimenting with a heat exchange system to power a radiator in one of his upstairs bedrooms. (There’s also a detailed explanation of a Wisconsin compost heating project here: Sure, this method is probably not practical for heating an entire home for most of us — but it might just provide a little extra heat for the hard-core composter. Watch a video of Towerton’s project here:

Candle-powered room heater: I’m a bit skeptical about indoor air-quality concerns and the relative carbon footprint of extensive candle burning, but some argue that this is a good source of emergency heat for those living in small, rented homes (which are usually the greenest kind of home anyway). Either way, it’s a useful reminder that we can meet our basic needs with a little ingenuity and some simple materials. Learn more from this video:

Use an underground server farm: OK, admittedly this one is easier to implement if you happen to be building the world’s largest underground city. But it’s still pretty cool. Helsinki, Finland, has been expanding its city downward, creating subterranean parking structures, data centers and more. Not only do underground data centers stay cooler because of the ambient temperatures, but the excess heat they generate is piped upward to heat city homes. District heating is actually fairly common in cities around the world. In Paris, for example, they’re exploring using excess body heat from the Metro to help heat homes. Learn more here:

Heat with nothing at all: Passive solar homes have been around for some time now. Most use the sun’s energy alongside other heating sources like natural gas or wood heat, but some manufacturers and designers are claiming to go a step further. Enertia, a manufacturer of what it calls geo-solar homes, claims that its manufactured solar homes can run on little to no supplemental heating or cooling except what is harvested directly from the sun. The “passivhaus” movement also has been spreading globally, with many homes built in cold climates that require no additional heat except for that which is generated from solar, body heat and wasted energy from cooking. Learn more at