There are some schemes, nothing quite as advanced as Y combinator. - Seedcamp http://seedcamp.com/ - Launch48 Launchpad http://www.launch48.com/launchpad/

But there are lots of places one could hang out and work on an idea: - Accelerator London: http://www.accelerator-london.com/ - London Hackspace: http://london.hackspace.org.uk

Shameless self-promotion, have a look around here about London based startup resources / opportunities (look at the schmoozing list!) - http://londonstartups.co.uk/

Another place to "hang out and work on an idea" is http://techhub.com @TechHub, a little like a KickLabs but without a fund. But Y-Com 'equivalents' would be Seedcamp (takes 8-10% of a startup) or The Difference Engine programme which is moving to Cambridge (just outside London)

I like techhub, but I am talking about a investment/office space for n number of weeks

I don't know of a YC-clone in London. There's Seedcamp and http://thedifferenceengine.eu up north.

an opening in the market perhaps