SciTE is a source code editor based on the Scintilla engine - a free source code editing component. In some sense, Scintilla is in regard to text editors what Gecko is in regard to web browsers - an engine that can be embedded into other applications. Like the Mozilla suite was originally built to demonstrate Gecko, SciTE was originally built to demonstrate Scintilla. Another text editor based on Scintilla is Notepad++.
SciTE is my favorite text editor since many years. There are much more advanced text editors of course. I have tried a variaty of them, but none of them really convinced me - they tend to drown me in a flood of features that I hardly ever need. For every-day use, SciTE turned out to be more efficient to me. Its philosophy is similar to that of K-Meleon - it is leight-weight, thus fast and little resource-intensive, and it is customizable through configuration files.
Following, I want to offer a personal modification of SciTE for Windows that provides syntax highlighting and code folding for K-Meleon macros:
SciTE176kmm001.7z, 588 KB, 2008-08-14
For installation, just extract the contents of this archive to the desired folder (you need 7-Zip) and set SciTE as the default editor for K-Meleon Macro Modules (KMM Files). Configuration files that make SciTE speak your language can be obtained from the scite-interest Google Group.
The terms and conditions of the License for Scintilla and SciTE apply.