set of 50+ industrial machines that are required to build and maintain a small, sustainable civilization. The open source aspect covers designs, instructions, schematics, budgets — everything anyone needs to know to build their own machines.
every game starts out as the handmade creation of the inventor, which eventually becomes a standardized and mass produced product; but sometimes the commercial versions of games are not available, too expensive, or just not nice enough
Nice little guide to building an IR transceiver - uses the USB port for stable 5V, but includes a link in the comments to a decent circuit diagram that uses a voltage regulator and therefore doesn't need the USB port for power.
fairly simple DTMF decoder to control solenoid door unlocker and connected it to phone (in this case a cell phone). NOTE:CALLERID would save the phonecall as commented on the article
MIT professor Neil Gershenfeld talks about his Fab Lab -- a low-cost lab that lets people build things they need using digital and analog tools. It's a simple idea with powerful results:
Weekend Project Podcast: Make simple radios to listen too. These were made with materials that they could get their hands on and were small enough to carry around in a big pocket.
If your own water is safe from heavy metals, but you still like the way water tastes when it's been through something like a Britta filter, there's an easy way to convert the filter to be reusable, saving a ton of waste and a bit of money.