Not really that happy with this response.I didn't expect you all to grovel, but i thought you might be a little bit interested, and i can pretty much guess if do tell you you'll say- we knew that.
I though one or two of the bigger boys with units etc might have had some interest.When i think back to some of the nonsence threads about fish tank heaters, and the viability of emersion heaters electrocuting us or not, and all of the really smart practical people (DIY matt etc) who've given this thought and come up with not very much at all.
Well due to lack of interest i'm not going to tell you- attention seeking indeed- when i came up with this i was asleep;it woke me up, and i couldn't get back to sleep again.
Of the sensible replies above an insulated unit and a heater works, and yes to defrost the hose sort of coil it around the radiater that's very close. But it's not the spark of genius i had that changes everything.