Upcase by thoughtbot - An online learning platform for developers - now free
Divuni - Daily questions - A social mindfulness platform
PracticeLinux - Learn Linux, Vim, Git, Tmux, Gpg and more
Notepin - Extremely simple note-taking + blogging ✍️
Enbitious - An online business learning marketplace that helps all ambitious entrepreneurs to learn & network.
MindFi - Meditate with open eyes. Be productive.