I'm looking for the semiconductor equivalent of ycombinator where EE/HW/CED types hang out and share URLs, projects, ask questions etc. Is there an equivalent?
Not a Y Combinator forum, but a treasure trove of analog circuit designs--mostly applicable to analog synthesizers and audio-- are available from Bernie Hutchins called "Electronotes" (your can purchase the entire set when he is back to accepting orders). Here is a link to his "free stuff" on the web:
http://electronotes.netfirms.com/free.htm
Offhand, the first thing that comes to mind for me would be the EEVBlog forums.