Having skimmed an article
comparing prices for various PC bits and cameras and things in France, Germany and the USA, I've had a quick look, and it seems it's noticeably cheaper to buy stuff from Germany and have it shipped over than it is to order it from the UK than it is to buy it here.
For example a Canon 28-135 IS USM lens, Bristol Cameras
normally have quite a good price on such things, charge £325+£10 shipping (cf. £375 from Jessop's). Digital Pear
(who I know nothing about, just found via Google) charge €426+€22.76 shipping, or a total of £303.80.
The Digital Pear price for a Panasonic AE700 projector works out to £867.71, the cheapest I've found in the UK is £999.