mate you could do this anywhere, there's people building cool software all over the world. See if you can find someone in Israel or Brazil or The Netherlands to sponsor your summer!
Yeah, that's definitely true! However, the only reason I mentioned SF is for conveniency as I live in California. There's brilliant people everywhere, and I would be glad to work in places like the ones you mentioned if I had the chance.
Ya man. You might have a better chance of lining something up if you post your github profile or a link to some of your side projects so people can see what level you're coding at