I can't remember where I saw this tip, but as someone who is always cold (and always battling my husband over the thermostat), I think it's a good one.
After baking something in your oven, instead of letting the oven cool down on its own with the door shut, keep the door open and let that warmth fill your kitchen. I just baked a pizza at 425 degrees and there's no way I'm going to let that amount of coziness escape out the vents.
Of course, don't do this if you have children or pets roaming about. Wait until nighty-night time.
P.S. Please forgive the dirty state of my oven.