Note 2020-07-24: Sincere apologies, this site has been down for nearly two years. The error was in the PNG conversion, due to the discovery of a ghostscript security hole. Everything should be operating normally now.
After math.b3co.com went down, I needed a new source for my online LaTeX conversion. This page converts LaTeX fomulas to png — it automatically adds the necessary \begin{document} cruft — on a one-off basis; script access is available through POST.
Optionally, you may pass ?xml as a GET parameter, and the results will be returned as
<?xml version="1.0"?> <latexresult> <lateximage location="_url_" source="pngtex.618034.com" /> </latexresult>
This way, you can avoid parsing all the surrounding cruft. Images are maintained locally, so you don't need to copy them to your home server (however, as a nice script kiddie, that's a kind thing to do).