oh err.. this was close...

[JohnP]

http://uk.news.yahoo.com/18/20090303/tsc-space-rock-gives-earth-a-close-shave-50a9c9d.html

[Mac]

dont know whats more scarry.
The fact that it was only 44000 miles away
or the fact that it was only discovered two days before it passed.

[Rick]

An asteroid which may be as big as a ten-storey building has passed close by the Earth, astronomers say.

The object, known as 2009 DD45, thought to be 21-47m (68-152ft) across, raced by our planet at 1344 GMT on Monday.

The gap was just 72,000 km (44,750 miles); a fifth of the distance between our planet and the Moon.

More: http://news.bbc.co.uk/2/hi/science/nature/7921279.stm

[Rick]

...but not quite as close as the one in this APOD: http://apod.nasa.gov/apod/ap090302.html