Dot Matrix Printers as musical instruments…
Paul from Dotmatrixsynth makes musical instruments out of printers, here writes – “I’ve got an ongoing project, reprogramming the firmware in these 1985 Epson LQ-500 printers to turn them into musical instruments. I originally just wanted to make a sort of homemade mellotron, but it’s evolved into a much deeper project. These printers (like all printers) have a computer inside that operates all the motors and handles the parallel port, etc. The software that drives that computer is all on an EPROM (a reprogrammable ROM chip.) I remove the EPROM, erase it, and reprogram it with my own software that I’ve developed by reverse engineering the printer and its computer.” Link.
Tomi writes – “This is a simple microphone preamplifier circuit which you can use between your microphone and stereo amplifier. This circuit amplifier microphone suitable for use with normal home stereo amplifier line/CD/aux/tape inputs. This microphone preamplifier can take both dynamic and electret microphone inputs (preamplifier provides power foe electret microphone elements). The idea of this circuit is to keep the design as simple as possible to be easy to build. That was my goal when I needed a simple external microphone preamplifier for my mixer. The performance of the circuit is nothing superior but can be used with many not so serious projects.” 
Mr Joshua writes “Here’s a video Tutorial from PYRO1234321 on how to make home made lock picks.” This is a great in-depth guide running 25 minutes. Also check out other lock-picking related videos submitted by 
Earlier 
Nice use of a mint tin! – “This site features projects and circuits for building stereo microphones from low-cost Panasonic electret microphone capsules. Included are Mid-Side, XY, and Blumlein microphone setups. In addition, there are interesting related circuits and links to sites with microphone information and parts sources.” 
The Goldfish Online has some really interesting LEGO logic gates – “…designed working NOT, OR, NOR, AND, and NAND gates. Using two NAND gates I have produced a NAND gate latch or Flip-FLop. The natural follow on from these is clocked logic, full-adders and ultimately a genuine “computer” device. At the moment all these gates essentially just demonstrators. They work, but because of the limitations that arise through gear slippage, the real practicable use is probably not that great.” The details of logic gates can be found here –