Observatory lasers could do it
The ones that bounce their beams off the Apollo lunar reflectors. This idea was even brought up by Buzz Aldrin for Cosmos 1, no less.
Just how far could Cosmos 1 be pushed - out of Earth orbit? Mars? M31?
Perhaps I am just being a bit romantic and thinking of Arthur C. Clarke's story "The Wind from the Sun". See it here:
http://www.ec-lille.fr/~u3p/textang/propha.html