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Does it work well as an exe icon? Is the word ‘ruby’ redundant with the exe’s name already [ruby.exe] perhaps?
-=r
Well, I’ve done it with the purpose to have an exe icon, as per this issue: Feature #1045.
IMHO that looks a bit busy, particularly on 16×16.
What about just the ruby for the .exe, and the ruby in a sheet of paper (as is common for source files) for .rb files? Not sure yet if .rbw should have a different icon.
Going a bit further, .gem files could be the ruby besides a package, but I’m afraid that could lead us into an endless stream of extensions to possibly relate to (.rake, .gemspec…)