Windows/Mac/Linux (Firefox): If you find yourself regularly selecting, copying, and then pasting text from your browser into emails, Email This! is a definite time saver. A right-click (or toolbar) menu lets you directly compose a new Gmail, Yahoo, or Google Apps web mail message with the selected text, or pass it into a mail client like Thunderbird or Outlook. Those options can be added to or whittled down, and helpful shortcuts (Alt+G for Gmail) makes text sending even quicker. Email This! is a free add-on, and works wherever Firefox does.