For these cases, I use a trivial program I wrote myself that just serves a specified directory over HTTP, optionally with basic auth. Most home routers have dy

For these cases, I use a trivial program I wrote myself that just serves a specified directory over HTTP, optionally with basic auth. Most home routers have dynamic DNS updates enabled, so the only instruction for the other side is "put $hostname into your browser window", sometimes followed by a "prefix it with http://" http://" if their browser insists on searching Google for that name. It requires some effort and knowledge on my side but tends to work pretty well for the other person. Even better when you have some instant messaging channel available where you can just send a direct link.