Many metro areas have a handful of them, for example in Austin (in no particular order):
* http://www.austinelectronicdesign.com/
* http://www.technologykitchen.com/
* http://www.concurrentdesign.com/
* http://www.produktworksdesign.com/
They all have their own specialties and pros/cons, but most of them deal with small startups to help bridge the gaps. As always YMMV so due diligence is required.