This guy has built an X-plane Ortho scenery for all of New Zealand, and distributes it via torrent. I've been meaning to try this out, but it needs some serious commitment, as it's a couple of huge files.
I have been looking at ways to distribute very large scenery files, so this is a good experiment. If any X-plane users are interested in this scenery, then now would be a good time to fire up a torrent -- I'm currently downloading the North Island (49GB), and there are three seeds. I'm happy to seed this for a week, once (and if) it's done, provided I get some help. Torrents rely on people actually leaving any downloads seeded after downloading, so that others can download from them. The experiment part is to see how many people actually seed, and whether it is 'self sustaining' -- while torrents are an ideal way to distribute large files, it wouldn't be a good choice if there weren't enough seeders to keep it active and available.
Here's the link to the scenery files-- note that I'm just downloading the North Island at the moment, so this is what I'm wanting to test -- if you have a very fast connection, you might want to try the South Island, so that there's are plenty of seeders when I get around to it:)
There's some info on torrents on the site if you haven't used these before. You will need a torrent client, there's a link on the scenery site as well.
The goal is to get a good group (10+) seeding with a fast connection, so that those with less than fast connections can also get a steady download by sharing with all the seeders.