I have been playing with a lot of AJAX enabled Javascript toolkits lately, like Mochikit and Dojo, but they are uninteresting to me and just contain effects web designers have been doing for years in a more combined framework like fashion. Plex however is interesting to me for many reasons.

Plex eliminates the need to write Javascript at the page level if you just want to use some cool effects for your web-page. The Javascript works in the background and Plex uses a DHTML/XMLish like language that gets executed on page load so there isn't any reason to clutter your page with Javascript. The actual Plex code reminds me very much of the code used to create Openlaszlo Flash objects, and Macromedia's MXML language, so combining these two technologies into a site keeps the learning curve way down and allows for more emphasis on design rather than programming. In fact the language is so similar to HTML it should be a very short learning curve for non-technical web designers.

Out of all the other Javascript kits I looked at Mochikit, Dojo, Mootools, and script.aculo.us are really nice as well. I like Plex so much though I plan to use it and contribute to it. If it at all interests you and you have some Javascript experience join in! I think Plex is really worth the time.

If you wish to use multiple toolkits Plex should play well with the other kits mentioned. All of these toolkits, including OpenLaszlo, are open source and free to use at no cost by the way.