Cookbook /
AddThisWidget  Embed the 'AddThis' widget to enable easy sharing of webpages on facebook, delicious, twitter, and other social networking sites.
EmbedTweet  a recipe to embed live tweets from using Twitter's oembed API facility (stable)
FacebookLinkInto  "Like" your wiki pages into Facebook.
ShortURLs  shorten URLs using, including a markup expression and a function for further coding
Twitter  Display twitter-messages and twitpics from any member in your page.
TwitterPost  easily post updates to your Twitter account via PHP functions (not currently working, as of Summer 2010 - twitter has switched to OAuth - recipe to hopefully be updated soon)