Latex formatting on iMessage?
It is actually possible to send arbitrarily complex LaTeX formulae with the help of LaTeXiT. The trick is fairly simple:


Enter the LaTeXiT preferences and, in the first tab, set the export
format as PNG. I also suggest to set the Scale to 250%, but this is a matter of taste.
Type a LaTeX formula in iMessage (not need to put the dollars)
Highlight the text, go to the iMessage -&gt; Services menu and choose any of the LaTeXiT services (for instance, the "Display" one)
Ta-dah! After few seconds, your Tex code will be converted into a PNG image, ready to be sent through iMessage!


PS: In case you don't see the service in the menu, go to your system preference and activate it: