It occurred to me that perhaps I was over-thinking the problem. Given that the Digital Classicist Wiki already contains a list of tools and projects, what about adding an <Opensource> tag so that projects who self-identify as open source would automatically be listed? As a test, I did this with WordChorus to produce a category list of self-identifying open source tools/projects:
Open source projects could then include their public repository source code locations on their Digital Classicist wiki description pages. Social coding sites like GitHub or BitBucket seem a good place to host the actual source code.