I've written this a while ago after I found out how images can be
added to the emacs modeline. I like being notified of things that go
on, and new dents is a good example of this, though `notify-send` and
an urgency hint don't always work for that.

This works:

[[!format el """
(add-to-list
 'global-mode-string
 '(:eval
   (unless (zerop identica-new-dents-count)
     (propertize " " 'display identica-active-indicator-image))))
"""]]

This will show an icon in your modeline whenever there are new dents,
at this time there dents will not have been loaded into the buffer, so
you'll have to refresh it, after which the icon disappears.

[[!meta date="2012-05-02 21:36:00"]]
[[!tag emacs elisp identica mode-line icon coding]]