To enable MathJax on this blog I navigated to Design>Template>Edit Html and then inserted the following script immediately after the

` <head> `

tag:
<script type="text/javascript" src="http://cdn.mathjax.org/mathjax/latest/MathJax.js"> MathJax.Hub.Config({ TeX: { equationNumbers: { autoNumber: "AMS" }}, extensions: ["tex2jax.js","TeX/AMSmath.js","TeX/AMSsymbols.js"], jax: ["input/TeX", "output/HTML-CSS"], tex2jax: { inlineMath: [ ['$','$'], ["\\(","\\)"] ], displayMath: [ ['$$','$$'], ["\\[","\\]"] ], processEscapes: true }, "HTML-CSS": { availableFonts: ["TeX"] } }); </script>

**For instance, the following LaTeX**

We consider the very famous formula \begin{equation} e^{i \pi} = -1. \label{eq:1} \end{equation} Given \eqref{eq:1}, we may deduce ...is typeset as

We consider the very famous formula \begin{equation} e^{i \pi} = -1. \label{eq:1} \end{equation} Given \eqref{eq:1}, we may deduce ...As far as I can tell, MathJax will render LaTeX inserted into comments as well. There is an extension for MathJax called XyJax that aims to provide commutative diagram support, but as of this writing I was unable to get this running on Blogger.