Car
Taxi
Plane
For people working on ActivityPub implementations I just wrapped up a nice chat with the folks of https://homebrewserver.club in Amsterdam (@manetta @rra and others). It was all via document editing and you can read the whole thing starting at line 188 in this document
It's a bit disorganized and I think they are going to digest it into a blog post or similar but for now this may be helpful to people who are puzzling their way through ActivityPub implementation!
