Earlier today I discovered Silverorange Lab’s SWAT Web application toolkit. This is an open source web application toolkit (PHP5) built by the guys at Silverorange.
Although this is version 0.0.4 I must say this is a really good set of widgets. It has almost every widget from the basic text and integer entry to Calendar entries to Pagination. From the sample code given it seems simple to implement. This is done completely with AJAX AFAIK.
A very handy tool. I will trying to use it in future projects of mine.
Rushi's Ramblings 