I am testing the jsMath package. Here’s how the authors describe it.

The jsMath package provides a method of including mathematics in HTML pages that works across multiple browsers under Windows, Macintosh OS X, Linux and other flavors of unix. It overcomes a number of the shortcomings of the traditional method of using images to represent mathematics: jsMath uses native fonts, so they resize when you change the size of the text in your browser, they print at the full resolution of your printer, and you don’t have to wait for dozens of images to be downloaded in order to see the mathematics in a web page. There are also advantages for web-page authors, as there is no need to preprocess your web pages to generate any images, and the mathematics is entered in TeX form, so it is easy to create and maintain your web pages.

Here’s an example: Euler’s celebrated product formula.
\[ \sum_{n=1}^\infty \frac{1}{n} = \prod_{p} \frac{1}{1-p^{-1}} =\prod_{p} \left( 1+\frac{1}{p}+\frac{1}{p^2}+\cdots \right) \]

So far I have mixed feelings. When I pull up this posting in Safari it looks great. On Firefox (on a Mac) it is a mess, using the provided server-side image fonts. On either the javascript needed to do the rendering loads pretty slowly. I could live with the slow loading, but the fact that rendering in Firefox is off gives me pause. On the other hand, after I installed the recommended TeX fonts on my Mac, the formula rendered beautifully.