Code
Below is a collection of on-line and off-line tools I've made (and there's more on GitHub).

ColorVariants
A web application for creating consistent color shades from any set of colors.
(online)
Windows Path Editor
The non-frustrating way to editor your PATH if you use a lot of command-line tools on Windows.
(GitHub page)
PowerSearch
The address bar is the new command line! Search any website directly from your address bar, with a simple configuration tweak to your browser.
(online)
Foldable CD Sleeve Generator
Generate a printable page that will fold up to a sleeve for 2 CD’s, including a cover image of your choice.
(online)
readTHERE
A bookmarklet to quickly copy/paste hyperlinks between different devices you own.
(online)
Subversive SVN Manager
Not to be confused with the Eclipse plugin of the same name, this Subversive is a web-based editor for SVN config files. Requires a Java app server.
(download at Google Code)
Freename
Batch rename any number of files using the power of your favorite text editor! (Recommended: power text editors such as Vim or Emacs)
(download at SourceForge)
LaTeX Equation Editor
See what your LaTeX equations look while you're typing them. No need to recompile your entire document.
(download at SourceForge)
Atomic Bomberman Launcher
Set up Atomic Bomberman matches at your LAN party in a heartbeat, without having to go through the crappy in-game config screens. Features map preview.
(download at SourceForge)
JavaScript color picker for MooTools
A translation of John Dyer’s Photoshop-like color picker for the MooTools framework.
(download here)