Converting LaTeX into Unicode for email

Following on from ipavlic's comment to the main question, here's a script that I threw together for almost exactly this purpose:

https://github.com/loopspace/latexToUTF

(My old PHP-enabled website has gone so I no longer have a "live" version, just the code on github. One day when I have a moment I will try to get it back up again.)

It was actually for typing unicode into webpage text boxes rather than email.

There is allegedly an extension to detexify that will give you the unicode instead of the LaTeX symbol, but I haven't seen a working version of it so can't comment further.

You may hit M-x describe-input-method RET TeX RET in Emacs. Here is a fragment of what you get:

\"x ẍ    \^h ĥ    \~e  ẽ    \=\AE Ǣ    \euro €    \doteq ≐    \square  □    \spadesuit  ♠    \vartriangleleft     ⊲
\"y ÿ    \^i î    \~i  ĩ    \=\ae ǣ    \e{e} ė    \equiv ≡    \subset  ⊂    \subseteqq  ⊆    \circlearrowright    ↻
\'A Á    \^j ĵ    \~n  ñ    \={A} Ā    \flat ♭    \frac1 ⅟    \succeq  ≽    \subsetneq  ⊊    \downrightharpoon    ⇂
\'C Ć    \^o ô    \~o  õ    \={E} Ē    \flqq «    \frown ⌢    \supset  ⊃    \supseteqq  ⊇    \ntrianglerighteq    ⋭

(By the way, this input method might be a nice way to actually type your emails - you type the TeX way, Emacs converts it to Unicode on the fly. And you don't have to use Emacs as your email client - even though it's a reasonable option - since you may configure it as an external editor in your MUA)

For Gmail users, the quickest way to convert LaTeX to a mixture of unicode + html must be the following addon called "GmailTeX":

http://alexeev.org/gmailtex.html

It is currently available for Chrome, Firefox, Safari and Opera. Once installed, you can simply type $G\rtimes_\phi H$ to obtain G ⋊_φ H, with φ displayed as a subscript via html markup.