@bamfic yeahhh... These are legitimate options for some people. But I can't easily change port forwarding settings on my end and I don't know whether my friend can on his, and either way this is not an option for other people I'd like to be able to exchange files with in the future.
Anyway, it shouldn't be necessary. We can do video-conferencing in-browser using only web standards these days, with single-click UX. Why can't we do file transfers?