I finished the text editor I was working on to learn OCaml.
It's (tentatively) called textmu. The selling point is that it's designed for multiple users, all SSH-ed into the same machine, to edit a document collaboratively. Otherwise, I basically made it a simplified knockoff of nano.
Source code is on github.
If you'd like to try it out (and don't want to compile it locally), feel free to get an account on my public server, tilde.
Also, an update. The OCaml folks said it's fine to publish their book, so you can now get your own copy if you want one (link goes to updated blog post with photos).