Please see my gallery of mathematical illustrations (careful: many of the images there are quite large GIFs; I would like to know about any bot that can compress those GIFs properly). Feel free to share your ideas for new illustrations on my talk page.

Here are some of the images I'm currently considering improving. Give me a shout if you can think of any others, or have other ideas for images.

Also need to make Dynkin diagrams with labels in the finite (not affine) case, and in the affine but non-simply-laced case.

This Week's Finds 285 by John Baez - mentions my plot of polynomial roots, exhibiting unexpected fractal properties.

The above picture on Microsoft's Seadragon, a convenient way of visualising large images online.

DeviantART user page

Polynomial roots on Github, a Haskell program to visualise sets of polynomial roots and corresponding iterated function systems (ongoing project).

Math Overflow