<div class="FTQUOTE"><begin quote>..... The only thing that works for me is external heat, like those microwave 'beanbags' ......</end quote></div>
<u>microwave </u><a target=_blank class=ftalternatingbarlinklarge href="http://morethanbeanbags.wetpaint.com/">beanbags</a> is also good thing for cold times. But here is what i'll say:
Drape a thick curtain over the front door which should be obvious.
However, don't worry about more heat for the house, wear more clothes. Layer up with a sweater over a tea shirt and then wear a fleece jacket over that. Wear tights or long johns under jeans or trousers, wear several thin pairs of socks rather than one thick pair.
Eat lots of thick, hearty soups, have hot drinks. When I was a child, we didn't have central heating at all, just an open fire in the living room. I remember the net curtains in my bedroom actually freezing to the glass of the window! We survived by the method I've said - just wear more clothes.