Purp - A smart to-do list and goal tracker app
Friend Hunt - Get desktop notifications when your friends comment on PH
Nirow - Habit tracking: Automated, Siri-ed, Calendar-ed, and More!
#MakerGoals - Live Twitter embeddable GIFs of your Product Hunt stats
Angstrom.Life - Dominate your life goals
History of Product Hunt - Learn community building from Product Hunt's example