how do i paint behind a radiator without taking the radiator down? their is only a small gap between the wall and the radiator but you can see some bits which i couldn't reach?

It might help you to buy a fitch, its a long handled brush that looks like this
http://www.decoratingdirect.co.uk/viewprod/r/RODWINSBS/

Try masking around the area if your struggling. Also if the pipes allow you can loosen the rad off enough to lift it off its brackets and lower it down on its face.

http://www.screwfix.com/prods/48379/Decorating-Sundries/Rollers-Trays/Harris-Flexible-Shaft-Mini-Paint-Roller-Kit-4

use one of those, gets right behide, its fexiable, darren if you havent got one get one i first got one 3 years ago, and ive replaced it when ive broke them, il never be without one now.

Cheers mate, i got a few of those and use them all the time, i think this guys problem is he cant get to a small area of wall between the top of the rad and probably a window, i find the fitch gets into small places nicely if you cant reach it with the mini roller, plus would presume he must be aware of the mini roller option.

Off subject i know but remember mentioning the white that goes on pink? i`ve stopped using it as it doesnt give a brilliant white, so now using supermatt on your advice i think, goes on a treat and finish is excellent, cheers.

no probs matie, supermatt is good stuff.
i alway think vinyl silk gives the best pure brilliant white fininsh on ceilings