Let’s take the commons metaphor for a moment (I’m not entirely happy with it). The Diggers seem to have been about reclaiming common land, and allotments were a shim for the lack of it:
http://en.wikipedia.org/wiki/Levellers
http://en.wikipedia.org/wiki/Diggers_%28True_Levellers%29
http://en.wikipedia.org/wiki/Chartists
http://en.wikipedia.org/wiki/Inclosure_Act
http://en.wikipedia.org/wiki/Allotment_%28gardening%29
Let’s ignore the commons metaphor for a moment and look at organisational metaphors for Free Software and culture. These historical models are ironised in Free Software, becoming inclusive rather than exclusive:
http://en.wikipedia.org/wiki/Guild
http://en.wikipedia.org/wiki/Trade_union
http://en.wikipedia.org/wiki/Cooperative
And ignoring both let’s look at social or political metaphors. The focus of Free Software is programmers, not programs. The name Free Software is like the name Free Society, don’t confuse the structure with the content. Meanwhile, Mackenzie Wark treats the GPL as cultural security, like social security:
http://en.wikipedia.org/wiki/Free_society
http://en.wikipedia.org/wiki/Social_security
But I think metaphors and precedents can be misleading.