HOT FARE: $601 roundtrip, including all taxes and fees - will get you from SFO (or LAX) to Sydney or Melbourne, Australia on United Airlines. Now that is a heck of a sale.
Details: Overall, there are few restrictions. Your outbound flight can be any day of the week between July 1 and November 30, 2009*. No advance ticketing requirements apply to economy class tickets. $250 fee + applicable fare difference if you make changes to the reservation before departure. Books into "K" class.
Have friends in the Big Apple? They can fly down under for just $60 bucks more! Visit the United Airlines website for more details on this sale.
*Sale t&c states outbound travel by December 16th, but the lowest fare class we found permits outbound travel no later than November 30.