Assorted robot projects. From object avoiding to object tracking. Check out the code samples and Eagle files available for download.
From DIY power supplies to those super simple BEAM robots to connecting an Arduino to a Raspberry Pi. You'll find some tried and true circuits along with some experimental ones.
As companies upgrade their data centers, they have to do something with their "outdated" equipment. This is a prime opportunity for us hobbyists to pick up enterprise class servers for over-the-top computing power!
This is a project that I started a few years ago...Implementing the seamless browsing power of Google Maps to WWII battle maps from the Library of Congress.