Odd as it may sound, I miss all the equations from my days in grad school, so I decided that what WordPress.com needed most was a hot, niche feature that maybe 17 people would use regularly:

\LaTeX

For those that don’t know, \LaTeX is a typesetting system particularly well suited for documents of a mathematical persuasion. It’s used almost exclusively by many technical, scientific and mathematical disciplines both in academia and industry. It also looks really good; I, among many, consider Donald E. Knuth a personal hero.

For those that do know, it’s now ridiculously easy to include inline \LaTeX formulas in your blog posts.

The syntax is reminiscent of \LaTeX‘s inline math mode: $latex your-latex-code-here$, and it allows you to produce most any equation. For example, the following code

$latex i\hbar\frac{\partial}{\partial t}\left|\Psi(t)\right>=H\left|\Psi(t)\right>$

yields

i\hbar\frac{\partial}{\partial t}\left|\Psi(t)\right>=H\left|\Psi(t)\right>.

Pretty sweet, huh?

To further whet your appetite, these few standards show a bit more about what’s now possible on WordPress.com.

\displaystyle\bar{M}=\frac{kT}{\Xi}\sum_N\left(\frac{\partial Q_N}{\partial D}\right)_{V,T}\lambda^N

G_{ab}^{(1)} = -\frac{1}{2}\partial^c\partial_c \bar{\gamma}_{ab} + \partial^c\partial_{(b}\bar{\gamma}_{a)c} -\frac{1}{2}\eta_{ab}\partial^c\partial^d\bar{\gamma}_{cd} = 8\pi T_{ab}

\displaystyle P_\nu^{-\mu}(z)=\frac{\left(z^2-1\right)^{\frac{\mu}{2}}}{2^\mu \sqrt{\pi}\Gamma\left(\mu+\frac{1}{2}\right)}\int_{-1}^1\frac{\left(1-t^2\right)^{\mu -\frac{1}{2}}}{\left(z+t\sqrt{z^2-1}\right)^{\mu-\nu}}dt

\square

UPDATE: There’s a new LaTeX on WordPress.com FAQ entry that describes the “hidden” size and color options.