Where can you find electrical outlets to power your gadgets? First of all, make sure they are fully charged before you leave and if you have spare battery, make sure it’s charged too.
Trains: Many train cars have electrical outlets by all of the seats, but many do not. While they may try to get you to sit in a particular car, sometimes if you just ask (nicely and politely) they’ll put you in a different car with better power. If not, look around the car they must plug in the vacuum somewhere. My experience is that near the center of the car under the seat (you just need to look, it’s relatively in the open) is an outlet with two plugs. You just need to get there fast since there might not be any more in the car (or have a splitter so you can share). In a pinch there is sometimes an outlet in the bathroom if you need a quick charge or want to have your laptop plugged in (so you don’t lose everything that is open) while you change the battery.
Planes: I’ve never seen an any kind outlet in the open on an airplane, even while walking through first class. I think I’ve seen some for shavers in the bathroom, but you can’t stay very long in there.
Airports: They’re all over the place but not always in convenient spots. Sometimes on the wall but not always by seats. Lots of times by the building support pillars but seats aren’t always near there. Many times where the staff and/or agents work but there might not be a good place to sit nearby. Look hard enough and you’ll find one in a good spot (in my experience), there is almost always one if you’re willing to sit on the floor.