Chabad.org
asknoah.org
An amazing video -- an interview about the Rebbe, concerning vaacum tubes and transistors:
http://www.youtube.com/watch?v=Vp4xyCF1GKQ
and here is part one of the clip (about the Rebbe working in the Brooklyn Navy Yard before he became Rebbe):
http://www.youtube.com/watch?v=EYNVql89yb4
Oneinfocus - Pictures with a Purpose
Some 3D pictures