Oh, those tricky Pirate Bay folks. The Teflon buccaneers have always managed to stay one step ahead of the law; for example, the site recently switched to the .SE domain to avoid a Megaupload-style takedown and three of its founding operators fled Sweden to avoid facing jail time and millions in fines. Now, a Pirate Bay user has released a zipped 90MB file containing the key components of every torrent hosted by the site. Basically, if Pirate Bay goes down, anyone with this file will be able to get it up and running again lickity split.
A Pirate Bay user called "allisfine" used a script to copy the titles, ID, file size, seeds, leechers, and magnet links for 1,643,194 torrents found on the site. There is a bit of confusion over the number of torrents, which allisfine admits him/herself in the torrent of the torrent site. TPB claims to have close to 4 million torrents. However, TorrentFreak makes the point that the 4 million-ish number includes torrents on public trackers that the Pirate Bay doesn't actually host itself, which could explain the discrepancy in numbers.
It's not quite a complete listing for each torrent, however. "I did NOT download comments and/or descriptions, since that would be too big and I didn't want it to be as complete as possible, but as small as possible," allisfine explains.
So, how is it that a massive site like The Pirate Bay can fit on a thumb drive? Magnet links. The site recently switched its torrents over to magnet links (also known as "trackerless torrents") and plans to ditch traditional .torrents all together sometime soon. These links are under 1KB each, which greatly reduces the site's footprint. For an in-depth explanation of the technology, check out this TorrentFreak article.
Who knows? Maybe the Library of Congress will fit on a USB drive sometime soon.