Linux game developer Bill Kendrick got his start programming on a Timex Sinclair: "This thing was about 7 inches x 7 inches in size, with a flat membrane keyboard, and 2 whole kilobytes of RAM ... all of the BASIC commands were available in one keystroke, thanks to a cool, context-sensitive cursor." I also discovered programming on a Sinclair, absconding with my dad's ZX81 shortly after he purchased it new in the early 1980s. The logo of my weblog is based on the groovy ZX81 keyboard (which weblogger Gary Turner spotted right away). I vividly remember sitting in my dad's apartment at 3 a.m., learning how to type commands on the ZX81's tiny multifunctional keyboard and using a television for a monitor, hunched over the device like a magician's apprentice learning how to cast a spell. If you'd like to work one of your own incantations, Jeff Vavasour's Sinclair 1000 emulator applet demonstrates the strangeness of the keyboard.
The ZX-81 was also my first -- handbuilt from a kit by my father. It was a great way to get hooked on programming. Your site's graphic is what jumped out at me on my very first visit, too.