Kepler 22b – okay, it's not the catchiest name, but NASA scientists are calling its discovery in 2011 "a major milestone on the road to finding Earth's twin".
It's the first planet anyone's come across that orbits a star (like our sun) in a 'habitable zone' - a zone where liquid water (a substance that lifeforms seem to be pretty fond of) could be readily available.
Kepler 22b is 2.4 times the size of Earth and orbits its sun, Kepler 22 (which has the even catchier alias of '11th Magnitude G5 Dwarf KIC 10593626') every 290 days.
That means a year on Kepler 22b is two months shorter than ours. Reckon they still get four weeks annual leave up there? Could be time for a star change.