[AccessD] Textbox special highlighting

Hello all:

I would like to have a consistent method of highlighting textboxes so that
a user knows that double clicking will result in the display of more
information.  Ideally, it wouldn't involve changing the background or
foreground colour, as I use these with conditional formatting for
displaying other information (order quantity is greater than on-hand
quantity, for instance).  Changing the border colour or thickness results
in some very ugly grid displays.

The ability to put a little triangle in one corner of the textbox would be
ideal - the way Excel does for comments.  Does anyone have a brilliant
solution?

Thanks,
Doug