First I got on the wrong train. I wasn't paying attention and apparently things on my line were behind; I got on the train that appeared at the right time, without checking the destination. Oops. Luckily I do that ride regularly enough that things felt wrong almost immediately after the line split from my usual direction. So I was only one stop out of the way and not all the way into SF when I got off the wrong train, but of course the train I would have liked to be on was on another platform and I had to wait nearly 15 minutes for the next one going my way to come through. And the trains coming out of SF have a lot more people on them, so I got to stand for the rest of my ride.
Which meant I got to my car about 30 minutes later than usual to start the drive home. I'm still driving counter-commute so traffic wasn't so bad. Just off the highway I noticed this weird hissing noise. My first thought was that the car to the right of me needed to fix something. Then as I was pulling off the main road I realized it was my car making the noise. I could tell it was coming from the front right but not what was making it when the smell hit me. That sickly sweet, almost cinnamony smell of burning coolant. I got to my apartment and parked the car - as soon as it stopped moving (so air wasn't blowing through) greyish smoke started billowing out from under the hood.
Luckily J was working from home and could come out and take a look at it. He had me start the car and poked around for a bit under the hood until he discovered a pinprick size hole in one of the hoses in the cooling system. The car is going into the shop today and hopefully we won't have to wait too long for a new hose, and (knocking on all the wood) nothing else is wrong.
It could have been worse, the hose could have popped the leak on the bridge itself. But it was one of those trips that makes you never want to leave the house again.