Interesting Chuck - I don't think the comparison with communism is erroneous, but I guess it depends on your definition of communism. Anarchists and communists have in most cases agreed about communism in it's ultimate form, but disagreed about how to get there i.e. whether the state is 'abolished' or it 'whithers away'.
I would argue that open source software is a great example of a common property which uses capitalist property laws to make sure it remains common (the GNU license). Some anarchists would actually argue that it isn't 'free' enough according to their tastes. There are various 'free-er' alternatives to the GNU license, but the real genius of the GNU license is that it compels users or modifiers of code to distribute products with source code included (however modified). Essentially open source software represents the accumulation of many shared cooperative inputs, which can then be shared, or modified by anyone else. It's the ideal communist model, really.