TeX input mode 
[Oct. 16th, 201211:35 pm]
Tobin Fricke's Lab Notebook

I've often wished for an easier way to enter unicode math symbols, for example by typing the LaTeX code. Instead the only way I know is to google for the symbol, which has got to be most complicated way of entering a symbol.
But I just found out that EMACS has a "TeX input mode", where you just type TeX symbols and they magically turn into unicode symbols.
For example, if you type
\forall x \in R, x^2 \geq 0
you get
∀ x ∈ R, x² ≥ 0
Awesome! If only I could get this input mode systemwide.
Invoke it with Mx setinputmethod and then TeX . I found out about this via this stackoverflow answer. 

