First video: Steve Zajac gives a very informative forum on his design of the upcoming $50 amp and speaker project. He gives a lot of great information on speaker design revolving around the Dayton ND90-8 driver.
Second Video: Dr. Wierzba shows off and explains how a theremin works. The theremin shown is a Theremax Theremin built by the AEE Theremin Team.
Third Video: AEE Guitar Pedal Team demonstrates a few guitar pedals using live guitar sound and an oscilloscope to show the change of guitar signal. These pedal kits were bought from generalguitargadgets.com and built by AEE.
Pedals in video: Tycobrahe Octavia, Dan Armstrong Orange Squeezer, Improved EA Tremolo and MXR Phase 45.