Late last night, the fifth largest BitTorrent search engine — BTJunkie — was voluntarily shut down by its owners. Like Mininova, BTJunkie was set up in the wake of Suprnova’s shutdown in 2005. BTJunkie is survived by its bigger brothers: The Pirate Bay, Torrentz, KickassTorrents, and IsoHunt.

The message on the BTJunkie site is fairly noncommittal: “We’ve been fighting for years for your right to communicate, but it’s time to move on.” Speaking to TorrentFreak, however, the site’s founder says that he shut down because of legal action against Megaupload and other torrent sites like The Pirate Bay. BTJunkie was one of the few torrent sites that had never been the target of legal action, and it seems its founder wanted to get out while he still could. With the Megaupload shutdown, unabated DHS/ICE takedowns, and pressure to pass SOPA and PIPA, who can blame him.

BTJunkie isn’t the only site to voluntarily cease operations Post Megaupload (PM) either. FileSonic and FileServe both disabled their file sharing features, QuickSilverScreen closed its doors, and Uploaded.to has locked out US visitors.

I know file sharing and pirate website takedowns are a fairly regularly occurrence, and where one site shuts down two will emerge from its ashes… but this feels different. Do the Feds finally have the upper hand on centralized file sharing?

Megaupload was a huge, huge win for the US government, way beyond anything that had come before it, including Suprnova, Mininova, and various other BitTorrent trackers. Megaupload was one of the largest sites on the internet and the largest centralized source of illegal files. It’s true that every file sharing site is run differently, and Megaupload made some mistakes, but the Feds are obviously trying to say “If we can shut down Megaupload, nobody is safe.” The Feds have effectively cut off the head of the beast — and what do you know, a bunch of sites have voluntarily closed their doors since. No other takedown has started a cascade like this.

The weaknesses of centralized file sharing have long been known. Copyright infringement is illegal, and when you squeeze millions of infringing files onto a single server it simply can’t end well. There are alternatives — decentralized methods such as BitTorrent DHT and the eDonkey network are impossible to shut down — but they’re slower and not as convenient as torrents or file lockers like Rapidshare or Megaupload. The truth is, these centralized services wouldn’t exist — and the founders of these services wouldn’t risk jail time — if there wasn’t significant demand.

File sharing is a huge part of contemporary culture, and at the same time our lives are governed by the corporate, globalized interests of Big Media. Therein lies the ultimate irony: Don’t forget, the Feds are meant to work for you. They’re paid with your tax money. Governments receive trillions of dollars a year in taxes, and yet it takes just a few million for Big Media to keep lawmakers in its pockets. Billions of people might disagree with draconian policing of copyright, but short of a revolution there’s nothing we can do about it.