Interestingly, software industry is heading in the opposite -- patent-free -- direction. It's called Open source software development, and it is tremendously popular. There are several impressive examples, such as the extremely successful Eclipse project http://www.eclipse.org, (btw, Eclipse is partly based on categorical ideas that engineers developed/reinvented from scratch). Another example is the use of open source software for commercial products by such giants as IBM. (Of course, building legal foundations for this is a separate story but somehow they managed it.) I have a feeling (though i maybe wrong), that patenting is becoming an outdated enterprise in the internet era. Z. [For admin and other information see: http://www.mta.ca/~cat-dist/ ]