The invention concerns using multiple computers to hold a conference. Under the invention, an application program can run on a single computer, yet remote participants can issue commands to the program. Remote participants can watch the program operate, because the invention replicates the ...http://www.google.de/patents/US5838914?utm_source=gb-gplus-sharePatent US5838914 - Collaboration system for allowing computer to draw annotation images on the output of selected program and replicating the annotation images on displays of other computers 
