SWeet 40hz!

Magic Eye was what I was looking for - I believe that was an actual commercial name.

There is some quite interesting stuff available through MAKE magazine. I've often thought of getting a subscription.

I saw this about a year ago and it really struck my heart.  My grandfather who passed away a few years ago, was a Amateur Radio Operator (VE3OJ) and used to tell me stories of how in his early years, he and his radio friends who were on the cutting edge of it all, rolled their own capacitors by hand using paper and wax to hold it all together.

When I was wee, he still had a lot of radio gear that ran on vacuum tubes.  I used to thrill over the tubes lighting up and lending a beautiful glow to the corner of the basement that was his "radio shack". He even had a few of those units that used a modulated glowing green display on the rounded end of the tube to help you tune in a signal.. These type of tubes have an actual name, which completely escapes me now. Depending on how close you were to the signal, a pair of opposing green wedges, on a phosphorescent disc in the end of the tube (like a primitive crt), would expand or contract.

This is a video I think he would have been fascinated with, and I'm glad to have been fascinated in his stead.