So here is something I just found. It is a compiler services that allows you to type in markdown in most RTF text fields, and then highlight text and have it format with a couple of clicks (or a hotkey combination). This is a Mac deal, but i’m sure something similar must exist for other OS
I just installed it, it doesn’t seem to work in Word (not that I would want to use that anyhow…), but it is working in my email client, and everything else I have tried so far. I am really happy to be able to use Markdown in my existing mail-client, this is really the only feature I found lacking, and was ready to try setting up a whole new mail client.