Today I started php|works 2007 off with a phenomenal course on Flex and how to use it with PHP-based services. This 3-hour course went surprisingly fast as we had all of 30 minutes of lecture, followed by a lot of hands-on coding and designing.
Flex 2 is a framework available from Adobe which allows you to create a graphical frontend for web services through Flash 9. Flex can use any web service that outputs XML or JSON, or can communicate in a binary AMF format provided through software like WebORB. The possibilities with Flex seem endless!
A great example of Flex is action is Yahoo! Maps. What's really cool is that you can combine Flex with the Adobe Integrated Runtime (AIR) and enable your application to be run directly from a user's desktop. The Flex Showcase has links to other sites that are using Flex.
Flex is available as a free SDK, or a less-than-free Flex Builder which greatly simplifies creating a Flex application. I must admit that after using Flex Builder, I would have a hard time using Flex without it. Flex Builder's GUI tools for layouts are quite handy, and the autocompletion is great for anyone getting started.
Since I don't feel proficient enough with Flex yet, I'll refrain from confusing anyone with code. I've heard of Flex as being "Flash for developers", and I can believe that a little more now that I've seen it. Flex is quite intriguing and this course was an awesome introduction to it!