We had to do this in 144 dimensions: https://blog.cloudflare.com/computing-euclidean-distance-on-...
I need to dig deep into highly optimized and perhaps distributed algorithms in this space - gotta deal with billions of high dimensionality items. The end result is probably going to be almost a survey from standard distance-based algos like hierarchical clustering headed into louvain methods. Anything "special" or maybe uncommon you like for this type of thing?