Recently I created an open-source project for integrating Google Charts API and Force.com to create custom dashboards. The project is a Visualforce component that leverages a custom Apex Controller, a custom dashboard record object, and Google Charts API to dynamically generate charts. Its pretty simple and can be used out of the box via "clicks not code". The codebase could be extended upon for lots of different use cases if developers so desire.
Here is a demonstration video:
And here is a code deep dive video:
You can access the repository here:
Hope you find some uses for this!