Most beautiful open source software written in c++ and using gtkmm/gnomemm
I was told that to be a good developer, you should read a lot of other peoples source code. I think that sounds reasonable. So I ask you, what is the most beautifully written piece of open source software, that is written in c++ and uses gtkmm/gnomemm, out there?

(Apply any definition of beautiful you like.)
Most beautiful open source software written in c++ and using gtkmm/gnomemm
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I was told that to be a good developer, you should read a lot of other peoples source code. I think that sounds reasonable. So I ask you, what is the most beautifully written piece of open source software, that is written in c++ and uses gtkmm/gnomemm, out there?

(Apply any definition of beautiful you like.)