Krioma.net

Yep, well you can now and this is a good step forward for future space based missions. This is crucial for future space based interferometers, be it detection of gravitational waves or future optical telescopes. Anyway what did this? NASA's Messenger probe, which is currently on the way to Mercury, and a group station in the US. They exchanged laser signals and could lead to some cool new developments in space based communications. Currently it is microwaves that are used but in comparision to laser communications this is crap, you can get much better data transfer rates with Laser beams. Anyway more can be found in this [BBC article]