3Dhubs is a Dutch website that provides a link between people who need 3D printing services and owners of 3D printers. They've reached their critical mass of hubs registered in several cities in the Netherlands and Belgium but London needs at least two more hubs to unlock. If you're interested, register your printer at...
http://www.3dhubs.com/london
They don't seem to be too fussy about actual location but it would probably help to be in the London area.
Cheers!
R
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