It used to be that there was a huge library of different window manager themes on themes.org / themes.freshmeat.net, but a few years back the site shut down and there doesn't appear to have been any attempt to archive it. Damn shame to see user generated content like this just vanish.
Ironically, it seems freshmeat for several years in response to the archive.org crawler was just serving empty pages with the message, "There is no need to mirror our content". Turns out yes, there was.
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