I moved away and am now planning to communicate with a friend over the internet and talk about mathematical subjects (e.g. via Skype). However the text blocks like "\int_G\omega..." in a chat window become more or less unreadable. It would be helpful to have a script like here on StackExchange, which translates the formulas.
Is there a good web page where one can write TeX code such that the other person sees changes live, or at least after pressing F5?