Regarding mapping statistics, we are still down to counting nodes and ways. For a mapping party in 2021 I spent three weeks experimenting with something better.
OSM Changes Counter is not well documented, but can count changes to objects of a given type, split them by city, apply weights (e.g. tagged node is worth more than a road way).
It also correctly counts roads splits and merges to output results in km — I think it's the only tool in all OSM that does that.
This one is not about OSM, but might be interesting to railway enthusiasts like me :)
GeoAlbum is a photo album with geospatial context. The script was inspired by @tmcw 's Big: keyboard navigation, data in html tags. You make an html page, include the library file, and it turns into an interactive album with numbered photos and additional layers.
https://github.com/zverik/geoalbum
I used it to share photos from a railway construction site along three years:
https://textual.ru/lk120430/