code_swarm is a software visualization tool showing source contributions made to a specific project. Here is an example of a visualization of Eclipse.
When all your troubles seems so far away…
An Introduction to TCP/IP, written so that most people should be able to grasp the concept.
HowTo: Create a Reverse SSH Tunnel is a handy guide for those times when you need access to a machine protected behind a firewall outside of your control, i.e. at work.
Gary’s weather forecasting stone
Learn 10 good UNIX usage habits and save yourself some time by doing it right the first time.
Elevator Psychology, fascination and hilarious all at the same time. (Flash required)
Logic Goats, even your children will understand how a CPU works thanks to the logic goats.
An lsof Primer for those of us who have happened to walk past this excellent little tool.
Miss iPhone Piggy tries to buy several thousand dollars worth of iPhones only to discover there is a one phone per person limit. (Flash required)
RBuild is a build system similar to Linux’ kbuild written in Ruby.
List of problems solved by MacGyver, found via xkcd 444.