Scientists are not very social you might think – why else would they choose to spend most of their time alone in labs surrounded by computers and rodents? Well actually, for centuries, scientists have shared their research and findings with each other and have used networks as tools to reach higher goals, through correspondence, meetings, consortia, societies, books, publications, journals, etc etc. In the early 60s, the Internet even was created by scientists who saw in it a great tool to communicate and share information on their research. It’s no surprise then that they are new social networks coming out every day on the web dedicated to scientists and their file sharing.
That being said, I think you will agree with me that internet-based social networks are amazing tools to interact with other people in your field, find job offers, share protocols and simply keep in contact with all of your colleagues. So I put together a list of a few networks that you definitely should register to. Some of them are strictly scientific networks and some of them are more professional or entertaining networks.

• Facebook, Twitter and Friendfeed – these three networks are very fashionable and are used by so many people that you almost have to be there! In most American conferences, Twitter is even used to share real time info about the sessions during the meetings.
• LinkedIn – with more than 70 million members in about 200 countries, this network is widely used for professional interactions.
• BiomedExperts – this one is based on scientific publications and is thus especially interesting for scientists who have published a few articles already. The site will connect you directly to your co-authors and the co-authors of your co-authors (more than 1.8 million scientists!!). I really like the email updates on my co-authors newly published articles.
• CiteULike – the idea is basically the same as the biomedexperts network, since it is based on articles published. The only big difference is the format.
• Nature Network – this one is really complete with a forums, blogs, hubs and many more ways to share info. It seems to reach 25,000 people at the moment.
• LabMeeting – this network is quite new and its aim is to facilitate the interaction of papers, articles and protocols between scientists, by downloading them directly through the site.
• I am Scientist – I register to this network a few weeks ago and it’s on invite only. I’m not sure how many users there are but it’s a nice site to keep track of your personal publications (it can be hard sometimes on PubMed to find a person’s papers, due to multiple people carrying the same name and other technicalities).
• Mendeley – Mendeley is not web-based so it’s a bit different from the others. It defines itself as the iTunes for publications and I think that pretty much explains everything!
• Researchgate, SciLinks, Epernicus, LabRoots – I never used these four networks but they seem to be very popular among scientists so you might want to check them out.

Of course, I’d love to have some feedback or suggestions for other networks you might find useful!