I also had a very unpleasant encounter with Uni$ys regarding licensing of a GIF viewer. I wrote a slideshow-type program that supports GIF and TIF and I was going to distribute it at no charge along with the source code (here ;)). Uni$ys wanted a $2500 fee as payment toward 'advanced royalties' for a license. I pointed out that this program was going to be free and there would be no royalties but that made no difference to them. They also said that the source code could not be published under any circumstances. I still can't believe this and I sincerely hope that they are not granted an extension on their patent.