Possibly the single biggest and most interesting time-suck I've seen on the internet to date. I've run across a lot of these things before, individually, and the ones I know are very awesome, which makes me think the rest of them will be too. One to sit down with when you've got time to spare, and want to be blow away by the artistic cleverness of others.

I adore OKTrends (OKCupid's stats analysis blog) out all measure. Especially when they prove bigots wrong with y'know, actual facts.

Photography heatmaps for various cities – things tourist take photos of compared to locals. Fascinating stuff.