This has been one interesting use case that I haven't really seen anywhere else in the #fediverse. Basically, it'll let you reply to a short-form post (e.g. Mastodon) or long-form post (e.g. #WriteFreely) with your own full blog post.

That post could either exist on its own out in the fediverse, or become a published post on your @write_as blog, while also being part of the conversation in the fediverse.