Замедление вращения Земли, линукс и перерасход энергии — казалось,
какая тут связь?

Но вот пришло интересное письмо от Hetzner:

During the night of 30.06.2012 to 01.07.2012 our internal
monitoring systems registered an increase in the level of
IT power usage by approximately one megawatt.

The reason for this huge surge is the additional switched
leap second which can lead to permanent CPU load on Linux
servers.

According to heise.de, various Linux distributions are
affected by this. Further information can be found at:
http://www.h-online.com/open/news/item/Leap-second-Linux-can-freeze-1629805.html

In order to reduce CPU load to a normal level again, a
restart of the whole system is necessary in many cases.
First, a soft reboot via the command line should be
attempted. Failing that, you have the option of performing
a hardware reset via the Robot administration interface.
For this, select menu item "Server" and the "Reset" tab
for the respective server in the administration interface.

Please do not hesitate to contact us, should you have any
queries.