It pays to plan ahead. Skybus, a new and rising airline, runs some great specials.
Here's what you'll find on their Promotions and Specials page right now:

10 seats for $10 each – on every flight! That’s right, each and every Skybus flight has a minimum of ten seats available for just ten dollars. It’s for real – but these seats go quickly, so be sure to book early and book often!

This means you'll have book far enough ahead to get a flight with a $10 ticket still available, but it could easily shave a couple of hundred dollars off your trip!
Their destinations are very limited (just 10 major citites), but you could always get close and then book a different airline to finish up your trip.

Labels: coupons/deals, misc.