The U.S. Naval Observatory has let it be known that one extra second will be added to 2008, right at the end -- 23:59:59 UTC on December 31, which is 6:59:59 p.m. EST.
Why go to the trouble? Because today's atomic clocks, for all their precision, can't otherwise account for the fact that the Earth's rotation is very, very gradually slowing, largely caused by the Moon's gravity and the tides it creates. It's less precise than the precise-minded would like. By international agreement, leap seconds have been added since 1972, at intervals varying from six months to seven years. The last came on Dec. 31, 2005.
The last day of the year will be twenty-four hours and one second long. What will we all do with the extra time?