Go Fucking Do It - Set a deadline and a price. If you fail, you pay.
Resolutions - A New Year's resolution a day until Christmas
Decidr - Make better decisions with quick A/B polls
AbTest.io - A free url shortener with A/B testing features
WebCodeSniffer - Validate your code for consistency with a coding standard.
appenguin - Turn the most complex web application or website to into an Android app in minutes, for free!