If I have a plane ride I almost always end up bored with reading and watching, and end up coding, but being offline really forces you to poke around in your tools and do as much introspection inside your language as you can, since there's no way to look up any reference or documentation while offline.
I regularly go to cafés here in town for an hour or two and sometimes I either choose not to connect, or just never get around to it because I'm too busy working and without the connection I forget I'm not connected unless I need to check something, and I don't get the interruptions of notifications either.