1π=√89801∞∑n=0(4n)!(n!)4[26390n+11033964n]
Right click on the equation and choose Show Source to look at the MathML.
In LaTex (I didn't need to edit this one): 1π=√89801∞∑n=0(4n)!(n!)4[26390n+11033964n]
Ramanujan's crazy-making identities get mentioned by me a few times in this debate thread on math-teach.
If you're not seeing equations for one-over-pi, click here for a picture of this blog post to see what you're missing -- provided Flickr still exists.