GB / London: Manna
GB / Edinburgh: David Bann
GB / London: The Gate
GB / London: SAF
A / Vienna: TIAN
USA / NYC: Candle 79
D / Berlin: La Mano Verde

Britain

East of England http://en.wikipedia.org/wiki/East_of_Englandat Wikipedia
(See also the book Vegetarian Guides - East of England)

 Cambridge
Rainbow Restaurant

Great Bricett, close to Ipswich
The Veggie Red Lion

Norwich
The River Green Cafe

Tring
Anusia / The Green House
(was recommended in The Good Food Guide)

VegCulture.net
USA / NYC: Blossom
A / Vienna: TIAN