Your phone is a powerhouse compared to even the most impressive supercomputers from a few decades ago, and most of the time that power isn't being put to good use. The Folding@Home project is all about harnessing unused CPU cycles from multiple devices and machines across the world in order to solve big medical problems. The Android app has been available for a few years, but it's now officially open source.

Folding@Home is a project from Pande Lab and Stanford University, but Sony has long been involved in the software side. It helped develop the Android client, which you can download now. It was only compatible with Xperia phones for the first few releases. Folding@Home uses a phone's processing power while it's charging at night to simulate protein folding, which is important to understand diseases like Alzheimer's and various cancers.

The core engine of Folding@Home has been open source for a while, but now the Android app and the web server component has been released as well. You can check out both on GitHub, if you're so inclined. Maybe someone will use this code as the base for another cool distributed computing project.

Source: Sony, Android source