Have you ever had trouble downloading large torrent files? It may be that the download is too slow, or that the network you are on (e.g. a school or company wireless network) has blocked torrent downloads. Most of the free file caching services out there don't accept torrents larger than 1GB, unlesse the torrent contains multiple small (< 1GB) files that can be downloaded over several attempts. Even those that offer 'unlimited' sizes have certain limitations on the contents of the torrent, such as hive.im which only accepts torrents with multimedia content.
I recently had to download a 3.9 GB torrent containing a software package and, no matter how thoroughly I searched, I could not find a torrent caching service that would accept it.
Finally I came across the BitTorrent protocol page, and started reading it in the hope of finding a clue to try to write some kind of mechanism that would bypass the university network limitations (maybe by port forwarding via a cloud-hosted app). There I came to know the concept of web seeding, where some distributors expose direct-downloadable files as torrent seeds in the hope of reducing the load on the original file server as more clients download the torrent and become its seeds.
Just out of curiosity, I loaded the torrent to a torrent client on my regular mobile data connection, allowed the peer discovery to proceed, and checked the seeds. Guess what? There were just two pure web seed URLs! I gave one URL to wget, and got a resumable direct download that completed in a little over an hour on an average 3-4 Mbps wireless network!
So, next time, before you go around complaining that your torrent is too big or too slow for downloading, just have a look at the torrent's seeds; if you have a web seed, you're most probably in luck!
(This, unfortunately won't work for multimedia torrents most of the time, as they are generally initially seeded by generous individuals who don't own web servers to directly host such files; but give it a try anyways before going for expensive alternatives, just in case!)