Have you ever heard about SciLink? It looks like a community site for scientists with LinkedIn-like profiles. You can build an online profile, search for relevant jobs or just create your own professional network under the Tree of Science feature.
SciLink™ is an online community with the goal of helping you to discover scientists, authors, and relationships.
SciLink’s network of 106,264,967 relationships is built by mining scientific data that exist on the web. Our databases currently contain over 5.8 million scientists and 14 million articles.
Also check out the official blog.