Was in Woolworths today and found a shelf full of the Cuprinol sprayable fence paint going for £3. I took it to the counter and asked them to honour the 50% discount on clearence products and they said "YES". I quickly bought 10 bottles - they still had loads. :-)
These are sprayable fence paint, very easy to use and quick.
B&Q is still selling it at £12.98.