The Sinclair ZX81 is 30 years old today. Here is a tribute to "the greatest program ever written".
20 years of Ryan Giggs in pictures
The first battle of America's next major war is being fought in Wisconsin
Oxford and Cambridge sound like better value...
Lovely bit of time-laspse astrophotography
Basketball star suspended for having sex with his girlfriend
Comments
Well, the original invention was for torpedos. Previously they'd required a direct cable connection, which was obviously rather limiting. Hedy Lamarr suggested, basically, using a player piano roll as a shared secret for unjammable/uncorruptable/nigh-undetectab
Aside from the military uses (which I can't comment on), pretty much all 3G/WIMAX mobile phones use that technique, as do the 802.11b/g/n WiFi standards. In those cases, the 'music' is from a PRNG with a known seed, and the number of channels is defined by standards, licences, and radio/antenna characteristics, rather than the number of keys on a piano, but it's the same principle as Hedy Lamarr's invention. Basically, every connected mobile device in use today owes her a little debt.
(And, obviously, she was also the inspiration for Dr Kleiner's debeaked pet headcrab...)
I love the HL games... but I'm really looking forward to Portal 2 at Easter.