Mac: We've mentioned before how Ctrl+Shift+V in Windows can strip the formatting from text and paste it in almost any application, but if you have a Mac, FormatMatch is the menubar utility for you.
FormatMatch strips all formatting from text that enters your clipboard as long as the application is running, so you can copy and paste using the standard Cmd+C and Cmd+V shortcuts to paste text in any application. If you copy and paste text between documents, browsers, and text entry fields frequently and don't want to reformat the text or use the format painter every time you do it, FormatWatch is a handy app to keep running in the background. It runs quietly in the background, and you can disable it at any time if you want to copy text with the size, font and other formatting included. Best of all, it's completely free.