Cross Platform Text Editors

These editors run on multiple platforms. Windows, Linux, Mac OS X, etc.

jEdit is a mature and well-designed programmer's text editor. It features syntax highlighting for over 130 languages, a built-in macro language; extensible plugin architecture with dozens of macros and plugins available. Supports a large number of character encodings including UTF8 and Unicode, folding for selectively hiding regions of text and every other feature, both basic and advanced, you would expect to find in a text editor.
[OS: Cross Platform] [Requires: Java] [Price: Free]
XEmacs is a highly customizable open source text editor and application development system. It is protected under the GNU Public License and related to other versions of Emacs, in particular GNU Emacs. Its emphasis is on modern graphical user interface support and an open software development model, similar to Linux. XEmacs has an active development community numbering in the hundreds, and runs on Windows 95 and NT, Linux and nearly every other version of Unix in existence. Support for XEmacs has been supplied by Sun Microsystems, University of Illinois, Lucid, ETL/Electrotechnical Laboratory, Amdahl Corporation, BeOpen, and others, as well as the unpaid time of a great number of individual developers.
[OS: Cross Platform] [Price: Free]
JED is a freely available text editor for Unix, VMS, MSDOS, OS/2, BeOS, QNX, and win9X/NT platforms. Although it is a powerful editor designed for use by programmers, its drop-down menu facility make it one of the friendliest text editors around. Hence it is ideal for composing simple email messages as well as editing complex programs in a variety of computer languages.
[OS: Cross Platform] [Price: Free]
Vim is a highly configurable text editor built to enable efficient text editing. It is an improved version of the vi editor distributed with most UNIX systems. Vim is often called a "programmer's editor," and so useful for programming that many consider it an entire IDE. It's not just for programmers, though. Vim is perfect for all kinds of text editing, from composing email to editing configuration files.
[OS: Cross Platform] [Price: Free]
Emacs is the extensible, customizable, self-documenting real-time display editor.
[OS: Cross Platform] [Price: Free]