Jürg Lehni, the creator of Scriptographer, have together with Jonathan Puckey developed Paper.js.
What it is? Well, I would say it’s a mix between Adobe Illustrator and Scriptographer on HTML5 Canvas.

Simply put, it allows you to do pretty much everything you can do with AI + Scriptographer in terms of scripting vector graphics, only this time through your web browser.
The best part is that it is highly compatible (save for a few revised and added features) with your old scripts as it is largely based on Scriptographer.

It even seems to be working on my iPhone 4.
It is very slow, though.