We camp in a 1996 Penine Pullman Towed by an 05 Ford Focus Estate.Full awnings with an awning extension.
Electric Space Heater. We use this to warm inside of the camper, often all through the night. For such a little guy it produces an awful lot of heat. It's got a thermostat which is handy when we want to leave it on during the night.
Gas Powered Space Heater. We use this primarily to keep us warm in the awnings, or when we don't have electricity. It runs on canisters that you can get for £1 each from many shops. Each canister gives bout 4 hours of heat at full blast.
Portaloo. Vital for those with children. It's a lot easier to sit the child on this than to trek them outside to the toilet blocks or a nearby tree.
TV Tuner Card. This is a fairly recent addition. It cost us £20 and plugs in to a computer via USB. We use the little antennae provided with it and the reception is excellent most of the time. So far this has been an invaluable luxury.
We rely pretty heavily on an electric hookup, we bring an arsenal of electronics with us. But we're geared up for a couple nights without.