An Advent calendar of small programming puzzles for a variety of skill sets and skill levels that can be solved in any programming language you like.

Flip through an archive of every Radio Shack electronics and computer catalogs from 1939 to 2011.

If you've ever come across "numbers every programmer should know", this article is an interesting read about real-world computer memory ballpark figures.

The Cyber Swiss Army Knife - a web app for encryption, encoding, compression and data analysis.

An extensive article about how to write your own raytracing software from scratch, provided you have some understanding of vector math.

A password generator inspired by XKCD 936 "Password Strength".

Over 1000 Public Domain assets for Physically-based computer rendering.

A free program for creating sound effects for games, music, videos - whatever you want! Works on Windows and with Mono.

A map displaying possible GPS jamming/interference around the world calculated from aircraft ADS-B broadcasts.