GoLocalBot. The project is closed - Platform for volunteers, NGOs, activists and crowdmapping.
Fine Tuner - Fine Tuner is a minimalistic guitar tuner that utilizes your device's built-in microphone.
GivingWay - Travel the world, do some good.
MyGuitarTuner.com - Online microphone tuner for guitar, ukulele, violin and other instruments. Tune by ear or using the microphone of your device. It's fast and accurate algorithm makes it one of the best online microphone tuners available.
Catchafire - Use your professional skills to help charities
LINGOT - Musical instrument tuner, LINGOT is a musical instrument tuner.