CiteULike is a web-based service that keeps bookmarks of citations following the same philosophy del.icio.us does regarding hyperlinks. Like del.icio.us, it is the ideal tool to share citations between collaborators and colleagues. "See what your colleagues are reading and let see them what you're reading ...". It exports to <goto>Endnote</goto> and to Bibtex. These citations can then be used with latex or openoffice.
Famous Maretecer's CiteULike feeds