Casey Bisson

An easy to use PHP class to send SMS messages. Does nothing on its own, but an implementation of it can be seen at <a href="http://library.plymouth.edu/read/222334" rel="nofollow ugc">my University’s library</a>, where they’ve used both <a href="http://about.scriblio.net/" rel="nofollow ugc">Scriblio</a> and wpSMS to <a href="http://maisonbisson.com/blog/post/12094/scriblio-feature-text-this-to-me/" rel="nofollow ugc">allow visitors to text information about a book to their cellies</a>.
The plugin is aimed at developers, so the best documentation is in the code, though there is <a href="http://maisonbisson.com/projects/wpsms/" rel="nofollow ugc">a quick introduction and some screenshts of it in action available here</a>.

wpSMS

A plugin to send SMS messages from other plugins. As easy to use as wp_mail().

vicchi

This plugin adds a ribbon graphic to the top right hand corner of your WordPress site to draw attention to and to protest against the draft UK Communications Data Bill which was unveiled in June 2012 by Theresa May, the UK Secretary Of State. The ribbon graphic links to an <a href="https://secure.38degrees.org.uk/page/s/stop-government-snooping" rel="nofollow ugc">online petition</a> hosted by <a href="http://www.38degrees.org.uk" rel="nofollow ugc">38 Degrees</a>.

WP Stop UK Communications Data Bill Ribbon

Add a ribbon to the top right corner of your WordPress site to protest against the UK's Draft Communications Data bill.

wpSMS vs WP Stop UK Communications Data Bill Ribbon