I've come to rely on this great little utility from Steve Miller.

Have you ever copied some text from a web page, a word document, help, etc., and wanted to paste it as simple text into another application without getting all the formatting from the original source? PureText makes this simple. Just copy/cut whatever you want to the clipboard, click on the PureText tray icon, and then paste to any application.  Better yet, you can configure a Hot-Key to convert and paste the text for you.  The pasted text will be pure and free from all formatting.