Build a Bare-Bones WordPress 2.8+ Widget
This tutorial is going to be a little more advanced than some of the fare around here, but in the end you'll have all the information you need to know to create your very own WordPress widget! And that's worth the effort, I think. However, you will need to understand a little bit of PHP for this to make much sense.

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Build a User Login Flash Widget
This chapter teaches shows how to utilize user management within a Flash application by building a User Login Flash widget. One of the most important aspects of the Drupal CMS is its ability to manage its users and protect the content of that site using a permission-based role system. (install acrobat reader to view this tutorial)

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PHP and DOM: The Way of the Widget
This article looks at the DOM extension and how it can be used to read and generate XML, providing new solutions for web page generation.

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Create a Google Calendar widget
This tutorial shows you how to display your Google Calendar events using PHP.

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Create an inbound link count widget with Yahoo
This free tutorial shows you how to count the number of incoming links to a page using PHP and Yahoo Site Explorer.

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A Twitter List Powered Fan Page
You can now create and compile a list of twitter users and make it easier for others to follow all at once. Also, at the same time, they expanded their API to include list management functionality. This allows us to use these new tools to create a widget that flips lists the other way around a fan page you can put in your sidebar, that allows your visitors to fill in their twitter name and join a specially crafted fan list in your twitter account .

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