I've always wanted to create a blog "platform" that's just plaintext or markdown files in a git repo hosted over a torrent-like network. By publishing, you automatically sign every post (commit) with a key, the fingerprint which can be used for lookup on a DHT. By "following" a blog, you're just cloning the git repo from peers and hosting it like a torrent. Things like fonts and colors get sorted out by the user, but the client has some built in theming options. Just roll it all in a simple app so mom and dad could use it.
Free hosting, censorship resistance, minimal styling blah blah blah. What's not to like?