Best site for watching airfare
Every travel-booking site from Orbitz and SideStep to Bing offers fare-tracking updates, but only Yapta does it for a specific flight at a specific time on a specific airline. So if you absolutely have to take the last nonstop flight out of Paris (Air France 008 at 7:10 p.m.), Yapta will send you an e-mail as soon as the price goes down. If you've already bought your ticket and the fare drops, the service will let you know if you're eligible for reimbursement. Caveat: Refund policies apply only if you book directly with the airline.