Mike from Mikes Electric Stuff guide to making high quality PCBs at home. Covers everything you need to know from what equipment to buy to which chemicals give the best results.
Collin Cunninghams video on circuit board etching gives a good demonstration of how to etch a pre-sensitized board using a lamp, photo-developer and etchant.
How to make clear glass PCBs. A video tutorial by CNLohr. Extremely cool looking finished products.
Great list of free books related to pretty much every programming language you think can of. It has books related to other computer related stuff too.
Land Pattern and dimensions for all preci-dip brand smd sockets and header pins. Download
USB : information on the protocol and using it with PIC microcontrollers
Information on the usb protocol with helpful illustrations.
Microchip Libraries for Applications – this is a series of programs contained in one package that deal with all kinds of interfaces and applications. It has a lot of USB examples in it also.
Another fairly in depth look the USB protocol from beyondlogic.com
A brief tutorial on using USB for embedded engineers
Visual USB software – This program is made for use with a special USB analyser device but you can download the program and look at some of the examples it comes with. These include usb transactions with a mouse, keyboard etc. Handy for getting a better understanding of what is actually going on
A tutorial on the HID( Human interface device) protocol. If you’re looking for information on HID and all of the associated lingo explained in simple English this is a good place to look.
Cool electrical engineering / science related GIFs
A gif illustrating how adding sine waves makes a square wave – very cool