Bookmark Tools
Summary: A set of bookmarking tools that are compatible and complementary (although the distinctions between Diigo and Shadows is yet to be determined other than Shadows lets you set up groups)
Other bookmark tools
Link: Jeteye.com
Summary: A tool that provides for quick packaging of web content (pages, images) to store, share, and retrieve through the use of tags (package tags, not individual site tags)
Link: Diigo.com
Summary: Seamless Integration of Social Bookmarking, Web Highlighter, Sticky-Note & Clipping. Diigo and Shadow are similar tools. Bookmarks are in real-time, but annotations and highlighting persist.
Advertising:
