there's a new feature here, enabling you all to easily post and format complex formulas. The trick is the new

**[ tex ]**bbcode tag.

Here are a few examples:

f(x)=\int_{-\infty}^x e^{-t^2}dt

e^x=\lim_{n\to\infty} \left(1+\frac~xn\right)^n

\left.\begin{eqnarray} x+y+z&=&3\\2y&=&x+z\\2x+y&=&z\end{eqnarray}\right\}

\large \left( \begin{array}{GC+30} \cos\frac\theta2 & i\,\sin\frac\theta2\\ i\,\sin\frac\theta2 & \cos\frac\theta2 \end{array} \right) \left( \begin{array} z & x_{\tiny-} \\ x_{\tiny+} & -z \end{array} \right) \hfill{300}

Feel free to test away in this thread

Also, there is a full syntax manual.