TI Calculator Simulator – A geeky labor of love, simulating one of the seminal 1970′s calculators. I’m awestruck that a machine with only 320 words of ROM and a CPU that’s minimal beyond belief could be so incredibly useful.
The Mighty Dictionary - A detailed explanation of how the Python dictionary works under the hood. The hash-attack freakouts are a good reminder of how useful understanding even the most black-box parts of your stack can be.
A Gauss machine gun – Sometimes I wish I was a physical engineer.
The Boolean Trap – “Code is written once, but read (and debugged and changed) many times” – words to live by.
Frak – Impressive abuse of the regular expression engine to match arbitrary sets of strings. It’s evil, but I’ve resorted to similar hacks myself to get good text-matching performance out of scripting languages