TESOL Masters--what opportunities lie beyond teaching/tutoring

Hi all,

I'm currently working on an MSEd in TESOL beyond teaching and tutoring is anyone aware of opportunites to do relevant work with that degree--i.e. textbook writing/ publishing academic articles--Is a PhD necessary for such work?  Is there any other opportunities someone is aware of?  Finally, what would be the best methods to inquire about such possibilities...

Thanks