gRaphaël is an open source JavaScript charting library that is based on Raphaël graphics library (WRD link).
It is capable of generating both static & interactive outputs including pie, bar, line or dot charts.

The charts are created with VML & supports the most popular browsers like Firefox 3.0+, Safari 3.0+, Opera 9.5+ and Internet Explorer 6.0.
There are some beautiful demos provided including the interactive pie chart & the dot chart.
Requirements: Raphaël graphics library
Compatibility: Firefox 3.0+, Safari 3.0+, Opera 9.5+ and IE 6.0+
DD_roundies is another rounded corners solution that is very easy to implement & cross-browser compliant.
This rounded corners script doesn’t use any images, works in IE6 without AlphaImageLoader & lightweight (3.62kb compressed).

Radius of the corners are not fixed & can be defined.
As the major problem for rounded corners lies beneath IE, this rounded corners script uses VML (inspired from Jonathan Snook’s solution). A possible future problem is IE8 -currently- does not support VML.
Requirements: No Requirements
Compatibility: All Major Browsers (except IE8)
Raphaël is a JavaScript library that facilitates using & creating vector graphics in websites.
It uses SVG & VML for creating graphics. As every graphic generated is a DOM object, you can manipulate them via JavaScript.

This graphics JavaScript library is very ideal for creating charts, images effects like rotation or reflection.
An example:
Creating graphics is much easier with Raphaël compared to writing everything from scratch as a circle can be created with:
paper.circle(320, 240, 50).attr({fill: "#223fa3", stroke: "#223fa3", "stroke-width": 3, "fill-opacity": 0.5});
The library currently works in all major browsers except Firefox 2 & it is still under development.
Requirements: No Requirements
Compatibility: Firefox 3.0+, Safari 3.0+, Opera 9.5+ and Internet Explorer 6.0+