Heated throw
The heated throw is the object the heat-the-person threads mention first and defend hardest, and it's easy to see why: a fleece blanket with a fine heating element woven through it, drawing around 100 to 160 watts — a few pence an hour at current UK rates, against the far bigger draw of heating a whole house for the same evening. Dreamland and Silentnight are the two names the UK reviews keep circling back to, and the recurring line in the long reviews is about the controller: several heat settings plus an auto-off timer, so it can warm up on high and settle to low without anyone falling asleep with it on full. The detail reviewers keep flagging is the feel — the good ones are soft enough to pass as an ordinary throw, with the wiring undetectable through the fleece. The honest caveats are that it only warms what it's touching, so the rest of the room stays cold, and that the cable tethers it to the sofa end nearest the socket. Most are machine-washable once the controller is unplugged.