The WMATA website (the people who run the metro and metrobuses) has the coolest feature - I don't know how long it's been around, but I discovered it recently when I was looking for something else. It's "Yesterday's service" - you can go on and look at how many people rode on a particular day.
But the most satisfying part is the list of everything that went wrong that day on metro and why. Ok, it's not like it matters, because this doesn't help you when you're standing on the platform with 50 million other people wondering where the train to Shady Grove is, but it's nice to look back and find out that a passenger was sick on a train at Farragut North. So it wasn't just metro being stupid, it was someone who was sick, and it's hard to be all that annoyed about that, yknow?