Slashdot has a bookmarking and tagging system, but it's a bit awkward.
Once logged in, you can bookmark manually at
They also have bookmarklets to do the same thing.
You can add tags, but onewordonly, no "multiple word" tags.
To edit a bookmark, the only way I could find was to go to Bookmarks->Recent and click on the "bookmark" link next to the one you want to change.
You can view your tags at http://slashdot.org/my/tags but you can't actually do anything with them yet.
There is some cross-integration between bookmarks, your journal, and story submission.
You can even get yourself a little "Slashdot Me" badge.
There's a FeedFlare to SUBMIT a Slashdot article, but I couldn't find one to bookmark an article, so I just made one.