Speaking of SVG, Lachlan Hardy pointed out the Raphaël JavaScript library to me, and I wanted to pass it along.
This library provides cross-browser dynamic vector graphics that generates VML for IE, and SVG for the rest of the world. Among the graphical elements you can create are paths, eclipses, rectangles, circles, and text, and be able to apply a number of transformations.
Included in the library web site is a playground where you can try the code out.