mitchellhislop

This plugin ties into Foursquare’s remote tip/todo functions, which in turn allow a website operator to 
easily embed the buttons. It was developed by <a href="http://mitchellhislop.com" rel="nofollow ugc">Mitchell Hislop</a> of <a href="http://smcpros.com" rel="nofollow ugc">SMCpros</a>

WP-Foursquare Todo Adder

This plugin allows a publisher to easily add a foursquare todo button to a post.

amitkeren

Unite Mobile Optimizer Menu will help your to create a sliding icon list dynamically where you can place on your website.
The settings menu allows you to easily choose which icons you want by putting the URL.

Unite Mobile Optimizer Menu

Unite Mobile Optimizer Menu will create a widget of icons to link to your sites.

WP-Foursquare Todo Adder vs Unite Mobile Optimizer Menu