id go to berlin instead just because its so much cheaper. london is extremely expensive, and so is frankfurt - yet it has many startups. (in fact most other cities that will be mentionned are much more expensive than berlin).

Then again, SF is in the US, stuff cost a lot less except for housing, and you don't have the possible euro crash looking at you every week (oh yeah i know, you've the USD issues, but they aren't looking _as_ bad these days)