SciTE

SciTE is an open source light-weight text editor for Windows and Linux operating systems.

It features a tab-based interface and built-in color markup for 30 or so programming and markup languages. It’s fast, and it lacks the bloat one might associate with other general purpose code editors. It’s available in various packages, one of which is a single 480kb Windows executable with no external dependencies, making it useful for situations where you need a good editor fast and without hassle.