I was very pleased to learn about this gallery of extensions to ggplot2. I hope it becomes an authoritative list. And I’m excited about some of the additional things you can do with ggplot2, including ggrepel for labels and two different options for plotting graphs (i.e., networks) with ggplot2.
I've recently migrated this blog, and the older posts might not yet be satisfactorily cleaned up. Apologies for the temporary mess.