My friend suggested that the FreeCache project may be useful here (
http://www.archive.org/web/freecache.php) but I've never tried it before.
re. BitTorrent, If you have Python on the Linux box and it's not behind, like, a NAT firewall or something then you can run BitTorrent on it easy
(BitTorrent was made to be cross-platform; Anything that supports the Python interpreter can run it).
I wouldn't worry about upstream speeds - I've run torrents off my machine, and I only have 20kB upstream. Once the ball starts rolling, people will get very good speeds (Assuming the downloaders don't disable their uploading. I hate leeching gits that do that...).
Downside of running it on your machine is that if your machine's IP gets changed, the whole thing stops working so it's not ideal. It also means the damned thing has to stay on all the time until you wanna kill the feed...
Anyhoo, this is the homepage:
http://bitconjurer.org/BitTorrent/For Linux+Python, goto the Download bit and get the Python Source (zip, tar, whatever).
Then you need to unpack that in your user area or whatever. There are instructions in there on creating a torrent feed in the "README.txt", and they're not too bad as opensource instructions go.
You don't actually need a webserver despite what it says (The webserver is just to get the .torrent file out to people so they can download, but you can do that by any means (ftp, e-mail, IM, IRC etc.))
If you try it and get stuck, post and I'll see what I can do (Assuming I'm still awake. I'm probably gonna go crash in a few minutes
)
