I can probably help (sent an email)
By the way, are you planning to keep those java applet thingies? I didn't find them very helpful, their illustration doesn't match the one I use "internally" (or when sketching things out on paper), so I suspect they could be improved. Maybe with Venn Diagrams, as Kevin says, maybe with something else.
Edit: it looks like what I was thinking of is called an eikosogram. An interactive eikosogram shouldn't be too hard to make in javascript.
Edit2: though considering the "speed is much more important than beauty" criteria, this kind of bikeshedding on details like that is probably not the most useful.
In any case, that sort of thing could be done more elegantly with the HTML5 Canvas than with Java now (whether matching the current style or using something like Venn diagrams). Applets feel clunky.
A huge revision of The Intuitive Explanation of Bayesian Reasoning is in progress, aimed at being considerably more accessible and hence with a lot more graphics. I need someone who can turn out versions of the illustrations that are technically accurate enough to try on beta readers, fast enough and reliably enough that I can ask for revised versions of the illustrations a day later if the beta reader says they didn't understand it. There is a Google Doc in progress which you would be given permission to edit, containing some hand-drawn attempts on my part to indicate what the illustrations should look like, and a number of finished illustrations from an illustrator who unfortunately cannot put in any further work on this job.
For this job, technical accuracy (i.e., if a ratio is 3:4, it should not look like 1:9), understandability, and speed is much more important than beauty - the idea is to get as quickly as possible to a working version with understandable illustrations that has been verified by the beta readers.
If interested, email me at yudkowsky@gmail.com.