I've seen many fics and prompts with Homeless Danny, and I've just had a thought: what's the safest place to sleep at night when you a) don't have a home, b) can turn intangible and invisible, and c) are not afraid of mortals' justice system since you're dead and it doesn't really apply to you?
Cops patrol the streets at night, but really, they mostly just pick a place and stay there until something happens, right? (I mean, I think that's right, I'm not very educated on the matter)
So, say Danny is in Gotham, and he needs a place to sleep, but it's the most crime-ridden city in the world, and sleeping out in the streets is cold and uncomfortable. And sure, he can climb into any car, but he chooses the cop car because, first, it's got a radio, so if the cops get any alerts about him (you can't tell me that GIW wouldn't use the help of local police, they are government agents after all), he will hear it first. Second, it's warm and cozy and soft. Third, and the most important: no one is going to look for him there! It's like hiding in plain sight but even better.
Or, well, it is, until one night the cop car he is sleeping in gets dispatched to some crime scene along with about a dozen others, and it turns out to be some trafficking rink that got busted or whatnot, and there are a lot of people who need to be taken to the GCPD station. So Danny, sleepy and grumpy because he was suddenly woken up, searches for the first still running but empty car, while staying invisible and intangible, and when he finds it, he just crashes in the back seat.
He is very surprised a few minutes later when the motherfucking Batman jumps in the front seat, and at least three of his sidekicks are trying to squeeze themselves in the back.
The Bats are even more surprised when they find a random teenager flickering in and out of visibility in the back seat of Batmobile, his eyes wide as saucers and Lazarus green.