Don Lancaster is a pioneer hacker. His site has a huge amount of practical electronics/computer hacks. One of his most clever hacks is using postscript to drive hardware in the real world, but there's plenty to go around.

I'm working on a design to automate my chickenhouse door open/close cycle (open at sunrise, close about 30 min after dark). Latch to keep the racoons and coyotes/dogs from getting in.
Thanks to msiegel for sending this clever hack my way (though the embedded webserver is a bit more than I need.) My henhouse door doubles as a ramp, kind of like a drawbridge. I'm having some difficulty figuring a critter-proof latch. I could add another actutator or two, but that increases the failure modes...

Searchable HackerSpace database. This page links to New Mexico HackerSpaces, but the site is global in scope.

Hack the garden! Use simple DIY techniques to increase yields through technology.

If your desk space is at a premium, making your O-scope do double duty is a damn fine idea.

From the page: " The Terminalscope is a full, bidirectional serial terminal that uses a PS/2 keyboard for input and displays 54x24-character output on an oscilloscope or XY display. It can be connected to a PC via USB-to-TTL adapter or directly to another microcontroller."

I'm cutting a few boxen from the herd, and have come up with a couple dozen old CD-ROM drives that need to be repurposed.

The hack I keep running across is converting the spindle motor to serve as a motor for an electric model airplane. Here's a FAQ on the topic.

The quick and easy hack is to change the winding from a delta to a wye configuration.

This interesting hack is a hybrid between the two, simply change a pigtail to change the wiring configuration.

Rewinding the rotor is a popular hack.
English rewound cd-rom motor instructions
links for rewinding cd-rom motors
Rewinding a brushless motor
The RCGroups.com website has many more discussions on this.

Now, if I could come up with some use for the photodiode pair, the electronics and the other motors in a few dozen CDROM drives...

Like that, only with a Coelacanth! (Or a Narwhal, for those with lots of space above their mantle...)

From the page: "This project uses the power of Linux to add brains to the Big Mouth Billy Bass. The goal is to use any Linux device--desktop or embedded--to make the Big Mouth Billy Bass say or act any way you want! That's right, we want to convert Big Mouth Billy to the least expensive peripheral you'll ever buy."

Everybody loves a Slinky, the tunable antenna!

Found this spectacular microprocessor blog on msiegel's excellent Categorian page. Theory and practice, philosophy and decapping. For those profoundly into their hacks.

Xtine66 sends this neat USB flash drive that looks like a cassette tape.
Very cool! Of course, the idea hamster in me can't resist taking it one step further: embed a tiny MP3 player into a Cassette Adapter so you can actually play MP3s in your clunker classic vehicle.

Altoids tins have become the standard project form factor for good reason: they're pocket sized, rugged, resistant to most moisture and impact abuses. This makes them ideal for project boxes, as has been well demonstrated by numerous makers. Rather than suing users for repurposing their iconic enclosures Ias is all too common the past few years), Altoids celebrates this creativity with a collaboration with maker pr0n site: HowStuffWorks.com.

Well done!

Commercial electronic stethoscopes are very expensive, ranging from over a hundred to over a thousand dollars. Several schematics exist on the internet, but why go through all the trouble when you can hack one for a few bucks using cheap consumer electronics?

The true |_3E+ will have done most of these.

From the page: "It is theoretically possible to add another bank of SDRAM chips to the XO laptop to double the amount of SDRAM in the system. ... Here are the instructions."