Well, I did it.
I'm now the proud owner of a single user #Mastodon instance. It's running as a #Docker container using LinuxServer.io's all-in-one image (https://github.com/linuxserver/docker-mastodon)
For bonus points I'm running it under #Dokku, which has meant some minor alterations to the init scripts, but means I've no need to worry about the Redis/Postges instances as they're all handled by Dokku.
At some point I'll push a repo with these alterations and some instructions.
@pieceofthepie What about mail server? Do these things work out-of-the-box?
I've read about installing a mastodon instance and find the procedure complicated, but the Docker image is a whole different league.
@wojciech I've not set up email yet. Since it's (currently) a single user instance it's not needed.
If I do sort it though I'll likely end up using mailgun. It's free for low volume and I use it elsewhere.
The LinuxServer image is super simple to use but won't scale as all the worker/instance counts are hard coded.
@splendidlemon So far, having been running for ~22 hours I'm looking at 360MB of disk and 22MB of database.
I think the disk can be managed with some settings I need to look in to as it's mostly cache. That's with maybe 10 or so followed accounts an a couple of followers.
jottr
pieceofthepie 
Wojciech
4D Spice