As LIGO and the other large gravitational-wave detection projects (GEO, Virgo and LCGT) move toward the next generation of detectors, it will be important to extend the gravitational wave network. Sources of gravitational waves can be located on the sky by comparing the arrival times of the waves at different locations, essentially a variant of triangulation. For a continuous wave source of the type searched for by Einstein@Home (e.g., a pulsar) the rotation of the earth and the motion of the earth around the sun effectively samples the arrival time at many locations with a single detector. But for short bursts of gravitational waves (e.g., the inspiral signal from a pair of neutron stars or the collapse of a stellar core in a supernova), multiple detectors at widely spaced locations on the earth are required. The planned network of two LIGO detectors located in the USA, GEO in Germany, Virgo in Italy and LCGT in Japan works well over part of the sky, but to be able to give complete sky coverage, a southern Hemisphere detector is required.
In the last few months, LIGO has teamed with the Australian Consortium for Interferometric Gravitational Astronomy (ACIGA) to propose to locate a next generation Advanced LIGO detector in Australia. If this project goes forward, the LIGO-Australia detector could be on-line soon after the other detectors mentioned above, and would help usher in an era of gravitational-wave astronomy.
For more details, you can find the proposal at http://www.anu.edu.au/physics/ACIGA/LIGOAust.html