Mark Holtom (aka Kingbeard)
Emil Jacobs - Collectifission@MarkHoltom Not sure about all of the UK, but in the Netherlands you can enter any train by holding your bank card against a reader to open an entry portal. That is pretty low barrier if you ask me.
tyx@tyx @MarkHoltom correct, but this is the lowest barrier of entry. Anonymous travel cards are certainly an option.