RSS
Diigo offers full RSS integration. You can use an RSS feed to keep track of
bookmarks, simply by subscribing to it in your favorite feed-reader, e-mail
application or web browser. There are RSS feeds for every user's bookmarks, any
tag and of course your Diigo subscriptions.
The RSS button can be found below the bookmarks (on the bottom of the page). Just do a right-click, save the link and paste it into your favorite feedreading application.