An amazing tool for visualising the solar system and constellation without a telescope (and astronomical knowledge or experience).

An alternative approach to understanding the universe.

What you can pay, and what you wished you can pay for what you really need.

All you need to look up on CPU horsepower used for personal computers, with a grain of salt, of course!

A very useful and informative site for tech-related issues in photography. You can download autofocus test charts to check camera finder focus accuracy.

I found this page while looking for a super fast hash function. It turns out to be a mine of useful technical and geeky information.

A very comprehensive guide to doing digital infrared photography. I ended up doing IR conversion of a Canon A510 and a Nikon D40x to play around with the idea of having IR false colours images.

If your Nikon DSLR has focus errors and you are sure that it's not the lens that's at fault, you might want to try this (at your own risk!).

This teaches you how you can build your own IR remote control for a fraction of the cost of what Nikon charges you. With a little imagination, you can go even further to build an intelligent controller that suits your custom needs.

Technical information of the Raspberry Pi GPIO pins

The simple dual transistor bidirectional level shifter by Jim Hagerman can be found in this article in PDF or this with scope traces.