vxJS
Advantages of vxJS
Small footprint. The core library weighs in with less than 30kB (uncompressed). XHR functionality adds another 6kB. The JSON functions are provided by the scripts of Douglas Crockford. The code size of the widgets varies, but hardly exceeds the 10kB mark.
Geared towards simplicity and speed. Most widgets come only with a "required" functionality, thus keeping complexity low. Some of the frequently used functions in the core library are optimized to a reasonable extend, thus making vxJS fast. Generated DOM content is kept simple, formatting left to CSS.
What vxJS does
Compatibility has been checked with IE6+, Firefox 2+, Opera 9.6+, Google Chrome, Safari 3+ and contemporary WebKit browsers.
Other browsers - particularly recent ones - are likely to work, but I haven't tested them with vxJS.
(Most of the time vxJS is used in Intranet applications with a limited range of clients; if compatibility issues arise, they'll be taken care of. I won't support for IE5.x or comparably old browsers - unless, of course, upon customer request.)
A "unified" event system has been added. It treats custom events and their listeners the same way as DOM events.
A simple but flexible effects library has been added to allow some eye candy, though the number of effects are quite limited (I won't put too much effort in effects, which either look bad, put a heavy load on the system, or are of limited use on webpages).
What vxJS lacks
A lot. Hoever, the important stuff is all there: Event handling, frequently needed functions for DOM manipulation, custom events. Enough at least to keep widget scripts short and easy to maintain.
Extensive documentation. But the scripts were never intended for being a general purpose library for a wider public. Inline comments are there, but little more.
Can I use vxJS?
Sure. Comments and suggestions are always welcome.
The download page offers a simple builder, that allows the combination of the various library elements to suit specific needs.
The library is constantly being updated and expanded.