I almost always use Chris' monospaced font trick. It's a great way to get an idea how things will finally look. Additionally, you have the opportunity to save as you go along; that can be invaluable toward keeping your sanity. Actually, I probably use a text editor or word processor to draft about 80% of my posts because of saving and spell-checking capabilities. Occasionally, when I think a table layout is really hairy, I'll use a word processor that gives me the opportunity to show all the invisible characters (tabs, spaces, line feed/carriage returns, etc.). It makes things easy to spot. Sometimes a global 'find and replace' speeds things your editing, too. Invisible characters can generally be shown by going to a program's preferences (options). Varying terminology is used, such as 'invisibles' or 'non-printing characters'.