display-time

[Jousimies]

(defface my/date-face
  '((((background light))
     :foreground "darkred" :bold t)
    (t
     :foreground "deep sky blue" :bold t))
  "Date face."
  :group 'display-time)
(setq display-time-string-forms
      '((propertize (format-time-string "%m/%d %H:%M %a " now) 'face 'my/date-face)))