osd is a little Tk library that is aimed at popping up messages on the screen when a hidden program needs the attention of the user.

Description:The osd library implements a new Tcl/Tk widget that presents itself as an (animated) notifier that pops up from one of the side of the screen in a direction that can be chosen. The osd features an image and an informative message.
Contact:Emmanuel Frecon, see web site