I have Drummer and Mastodon hooked up. You can create a thread in the outline structure in Drummer and then click an icon in the left margin to shoot it over to Mastodon. Here's an example of such a thread, in Mastodon and a screen shot of the outline that came from in Drummer. It's been a while since I added a feature to Drummer, and it seemed the new Mastodon capability in my toolbox seemed like a good opportunity to do that. I'll write up a howto for this shortly.