One thing I know that doesn't work at least when ordering from Amazon - whether they have changed the rules, or if it was only an old wives tail in the first place - is marking parcels as 'gift'. I bought three digibook BDs last year and got stung for £18 even though I sent them to my parents' address as 'gifts'. In effect it would have cost the same to just have bought them from Amazon UK Marketplace.
To be honest, I don't mind paying the VAT as even taking that into consideration you can often save a quite a bit on buying the same through UK importers or ebay, it's just the massive 'handling fees' that RM charge you. On the rare occasions that I have been charged customs, RM's fees are usually 3-4 times what the VAT charge was.
