Diigo*:[PR6] “Digest of Internet Information, Groups and Other stuff.” Web 2.0 style text-based interface, bookmarks and annotation using Tags. The toolbar gives highlight and blogging support. Update! UI redesigned.
Some Features: One click bookmark with custom Tag. One click copy. Related Tags(+add and remove), Search(My/Community/Tag/Full Text). In page Advanced Search(Anywhere/tags/title/URL/highlights/Text/comments/without). Direct Links. Public/Private Bookmark or only notes/highlights, Inbox(follow user and tags), Bookmark username, RSS, mail, batch checked bookmarks( public, private, edit, extract highlights, send), Tags, Tag Cloud that is also a Tag editor. Image bookmarks have thumbshots(toolbar required). Cache copy.
Tools: in page Bookmarklet (annotate, bookmark & forward) for IE, Firefox, Safari and Opera. Import directly from browser bookmarks, file and del.icio.us. Ajax Linkroll generator with options. Add to Diigo blog footer buttons and code. [button code]