[anotherperson]

I kind of like Mathematica’s syntax of ESC-shorthand-ESC for inputting non-ascii characters. Not quick, but definitely readable.

[stevenbedrick]

+1, +1, +1. Mathematica's fabulous in this regard- its InputForm -> FullForm -> StandardForm/OutputForm pipeline is The Right Way to handle this problem, IMHO. You can use its ESC-shorthand-ESC/etc. syntax to enter your code in StandardForm, or you can type it longhand using InputForm- and it all gets represented internally the same way.