PUBLIC MARKS with tags textarea & editor

Here is EditArea, a free javascript editor for source code. (That is no way a WYSIWYG editor).

CodePress is a code editor with syntax highlighting written in JavaScript that colors text in real time while it's being typed in the browser.

widgEditor is an easily installed, easily customisable WYSIWYG editor for simple content. It replaces existing textareas with an improved editing pane using JavaScript, therefore if you don't have JavaScript (or your browser doesn't support HTML editing) it degrades gracefully. Try it out by typing below, and submit to see the processed output.