The Secret
Life of Machines - A stuffy professor builds cool gadgets to show
 how everyday machines work. One of the best shows ever about engineering. 
 Absolutely! Their style of presentation was great: taking stuff apart
 to show the viewer exactly how it works and making models out of junk
 to illustrate the theory. They had a knack of explaining things in a
 way that made sometimes complex concepts really easy to understand.
 The shows are also full of anecdotes, and the fact that they didn't
 bother reshooting scenes which went less than perfectly made for great
 entertainment.
 It doesn't look like one can easily obtain a hard copy of the shows,
 but all three series are easily found on the web and there are
 snippets all over YouTube. There's some nice on-topic footage in the
 episode about the word processor, including a demo of a Ferranti
 Pegasus playing music: 
 
Last time I looked, Tim and Rex were actively encouraging people to
share the show on the 'net.
Peace...  Sridhar