Grumble - literally got the last of the bits needed to replace my missing master key today! Guess I'll have to keep it old-school (but original :) )
On a side note, I was in my local Sainsburys (Winterstoke Road, Bristol) yesterday and asked how much they'd charge to cut the blank. They said that they actually charge for the blank rather than the work itself, so it would be free as I was supplying my own key. However, there work would not be guaranteed. Free is free is free mind, so might be worth a punt at yours!