It's tech week so I really don't have an awesome post about how theater is like writing.
I did see this http://gu.com/p/2cdt8. It is a video of an actor having their brain scanned while reciting lines from a play versus counting. It's pretty cool. Also Fiona Shaw is the actor having her brain scanned so check it out.
It made me wonder what a writer's brain scan would look like when they are writing.