Thanks a lot for answers so far.

I forgot to add that we are talking about sharing over entire continents not LAN, but you probably got that from the post anyway.

Some do have dynamic IPs I think, so that would be a mix of both.

We were talking about using DC to do this, but DC is a download same file from one person at a time program and has no swarming abilities. Phex would be great, in the sense that let's say I have a file that several people on the network want, but I have slow upspeed. I could then choose to just upload to the fastest peer and he could start spreading to the rest right away.

BitTorrent is a great way as well, but there is no chat, and trying to incorperate a private chat into a client would probably get us banned from the sites we love so much. Also uploading probably 10-30.000 .torrent files per person would be done sometime next century.

The ability to be able to download entire folders is very important as well.

I think someone with great coding abilities should take up this challenge, it would be a revolution in private filesharing