I use one called Blogofile[1], but it is entirely local. You basically give it the posts as markdown/restructured text and it generates the entire site as static HTML. I'm sure you could use it as a starting point to start the service you just mentioned, instead of having it read the posts from disk have it read them from a database.
The thing I like about static generators is that I don't have to worry about a programming language being present on my hosting site (http://funcptr.net is blogofile, http://bertjwregeer.com/ is Poole.py[2]) and the overhead is a lot smaller, since all I have is static files there is a lot less worry about accidentally causing CPU spikes, or a database being overloaded, and using sendfile() one can very quickly and efficiently serve up HTML files to clients.
The thing I like about static generators is that I don't have to worry about a programming language being present on my hosting site (http://funcptr.net is blogofile, http://bertjwregeer.com/ is Poole.py[2]) and the overhead is a lot smaller, since all I have is static files there is a lot less worry about accidentally causing CPU spikes, or a database being overloaded, and using sendfile() one can very quickly and efficiently serve up HTML files to clients.
[1]: http://www.blogofile.com/ [2]: https://bitbucket.org/obensonne/poole/overview