See which hashtags have recently been used on a specified Twitter list. Enter the list URL in the form: http://twitter.com/USERNAME/lists/LISTNAME (capital letters not required - for emphasis only).

Programme your own suite of Boxee channels using the delicious social bookmarking tool. Bookmark Youtube user pages, playlist pages or video pages, BBC iPlayer genre pages, format pages, or video pages, or simple MP3 files to your delicious account using the tag 'delitv'; then enter your…

A structured feed of video content from The Economist. Bookmark this page to a delcious DeliTV tag, and watch Economist video content via Boxee. Howto: http://ouseful.wordpress.com/2009/09/02/delicious-tv-personally-programmed-social-television-channels-on-boxee-preview/

Search over recent tweets using a particular hastag, and get a listing of who's recently been tweeting using that tag most heavily.

A pipe to augment your twitter feed with info from the twittervision API. See it in action at: http://ouseful.open.ac.uk/geotwitterous/