I'd like to see different ways to display the information in the Winter Bash leaderboard. The leaderboard has lots of data, and changes frequently, so it would be infeasable to me to generate these views on my side. However, the StackExchange servers could probably generate them easily.
First, let me tell the two ways I can already group this information.
Group by site, then user sorted by number of hats. This is available from the Leaderboard if I choose a particular site, eg. list by users on Sci Fi & Fantasy SE. This lets me answer questions like: what users have the most hats on a site, what users does a particular user have on a site.
Group by user sorted by number of hats. This is available from the Network-wite Leaderboard. It lets me answer questions like: which users have the highest number of distinct hats, which hats does a particular user have anywhere, and on what sites they have those hats?
I'd like to see the following views. They would be useful even if some of them would be restricted to non-secret hats. If some of these views are already available, please tell me where in an answer. If not, please implement them.
Group by site, then hat, then by user sorted by date first earned. This would let me answer questions like: on Sci Fi & Fantasy SE, which hats have we collectively earned; how close are we to start getting "Every! Pony! Gets! A Hat!" hats; on that site how many people have earned each hat; who earned that hat first on that site? This would be analogous to the per-site list of badges, but for hats instead of badges.
Group by hat, then by user sorted by date first earned. This would let me answer questions like: globally, how many users have earned a particular hat; which users are they; who earned this hat the first time?
Group by hat, then by site, then by user sorted by date first earned. This would let me answer questions like: on how many and which sites have this hat been earned; how many users have earned it on each site; on which site have the highest number of users earned it; on which site is it still unearned?
