Lastly I'm not that active on this site, but I made a map of CogSci.SE, basing on tag co-occurrences.
Some more description e.g. on a respective post on meta.math.SE.
The project is on GitHub: https://github.com/stared/tag-graph-map-of-stackexchange/wiki (feel invited to tweak the plot to your taste).
I hope you like it! (For site promotion or just some insight.) :)
And before anyone asks, colors are for graph communities (groups of nodes which have a lot of connections between each other).
aarthi at stackexchange dot com
for me, and I'll send you the CSV!