Displaying images "outside" the layout

[Lars Ingebrigtsen <larsi@gnus.org>]

I've been thinking a bit about adding the possibility of adding image
previews to dired in a more similar way to other file browsers.  There
is image-dired and friends, but they require batch processing and are
kinda awkward.

What I'd like to see is that when you place point on an image, or you
issue a special new command, Emacs would make a preview image on the fly
(like all other file browsers), and it would display this image in a
convenient way.

Inserting the preview into the buffer would be the easiest, of course,
but where?  On the current line would be obvious, but would make stuff
move around, since image thumbnails would be taller than the lines are.

So here's my question: Is there a way to display images in tooltips?  I
tried the obvious, which is using a string with a display parameter that
points to an image in `help-echo', but that didn't work.

-- 
(domestic pets only, the antidote for overdose, milk.)
  bloggy blog http://lars.ingebrigtsen.no/