Kaboom by Hotspot Shield - Share messages & photos that disappear on any social network
Typora - A minimal Markdown reading & writing app.
Hamster Pad - A social network built on top of Slack
Dillinger - joemccann has 95 repositories available. Follow their code on GitHub.
Doof - Share your hopes and dreams.
StackEdit - Full-featured, open-source Markdown editor based on PageDown, the Markdown library used by Stack Overflow and the other Stack Exchange sites.