http://www.youtube.com/watch?v=z4Y7R54giqM is a video of this system in action.

From [comp.lang.tcl]:

"The TACO Shell, or TACOS in short, is a replacement [Windows]® Desktop Shell
aimed at supporting shoulder-to-shoulder collaboration around tabletop
displays. TACOS is able to rotate each window separately so as to
facilitate interaction and visualization for all users present around
the table. TACOS also offers a number of additional features to support
the management of windows on the desktop: transparency of windows,
reduction of windows to their title bar, quick window orientation
shortcuts, etc. 

[...] the whole system is built with [Tcl/Tk]. I ([EF]) use [TkZinc] as a replacement for the regular [canvas], which gives me the ability to rotate objects and control their transparency. I also use a custom capture [DLL] for getting the content of the windows. All the rest is a lot of [Tcl]-glue, some of it being available from my home page [http://www.sics.se/~emmanuel/?Code]"

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[Category Application]