While the RIAA has been trying for years to get Pirate Bay offline, it seems that the weekend's leap second fiasco managed it.
Over the weekend a number of key sites went tits up because they were not programmed to cope with the leap second.
In Pirate Bay's case it was due to a bug in the NTP daemon, which caused crashes of Debian based Linux machines all over the world.
TPB posted a note that it would be back as soon as it could find a sober admin to fix the problem and it assured users that it was not a DDOS attack or a raid of any kind after all.
The reason this is done is because the atomic clock standard we use has a slightly different rate than the rotation-of-the-Earth based Coordinated Universal Time system. Since these two years are so out of whack, humanity has to compensate by throwing in the odd leap second.
Last time there was a leap second there were a few problems for systems admins. This time people like Red Hat released a few patches to make sure that nothing went tits up. However there are reports of other companies having similar problems.