This is brilliant - 'Lost' easter egg on Kayak site. Search Kayak.com for a one way flight Sydney to LAX on 9/22/2010. This is the result you get.
Genius fan based transmedia in action.
UPDATE: There's a second easter egg. The easter egg references a flight from LAX to Guam. If you search for it on Kayak (one way) for the date Jan 21, 2011- a mythical airline called AJIRIA will offer you a fare at for $4839 which is the beginning of the secret code that keeps appearing on LOST.
If you click on the airline you get sent to the AJIRIA site.