Death to trailing whitespace

Whitespace at the end of lines is farily annoying, and wastes space. It also generally annoys other developers if you send patches that introduce white space.

Luckily, emacs can show you with big red blocks where you've left whitespace behind. I think everyone (who hasn't already :) should add something like

(mapc (lambda (hook)
      (add-hook hook (lambda ()
          (setq show-trailing-whitespace t))))
      '(text-mode-hook
      c-mode-hook
      emacs-lisp-mode-hook
      java-mode-hook
      python-mode-hook
      shell-script-mode-hook))

to their .emacs file right now.