17 February is WWF's National Sweater Day (shouldn't that be International Sweater Day?) and they encourage everyone to "turn down your thermostat by 3°C, and put on a fun sweater."
Let me tell you something, Mr. WWF: my apartment is usually at 5-10°C, and I don't think I can fit any more sweaters over the three I usually wear. I think I'm doing my part for the war on wasteful heating. My roommate and I deserve some sort of special award for martyrs, really.