Today the entire world will get an extra second. Spend it well. Why, you ask? At 17:59:59 (5:59:59 pm) our time, the Earth will get a Leap Second.

What exactly is a "leap second" and why do we even need one? According to Wikipedia:

leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC) in order to keep its time of day close to the mean solar time, or UT1. Without such a correction, time reckoned by Earth's rotation drifts away from atomic time because of irregularities in the Earth's rate of rotation. Since this system of correction was implemented in 1972, 25 such leap seconds have been inserted.

Well, there you have it. Although adding an extra second probably won't mean a whole lot to you, it is kind of a big deal. Why? The Earth's rotations are actually slowing down. Translation: our planet's movement is screwing up our time system.

So what do you plan to do with your extra second of time?