For this day, 2collab seems to be not very popular among the researchers, but I hope it will change soon.
26 November, 2008
I came across an interesting service - 2collab, a tool for scientific bookmarking, sharing and collaborating. It looks like an academic analogue of delicious. This project was started by Elsevier, and therefore any article from Elsevier journal may be immediately bookmarked using an "add 2collab" button at the journal website - and all the bibliographic data will be automatically transferred. Unfortunately, at the moment no other journals have such buttons. Of course, one can bookmark absolutely any webpage, but in this case one should write up the bookmark description (title, etc.) by hands, which can take a while.