If you've been in need of a vacation but were holding out because of costly travel expenses, Frontier Airlines has a treat for you. With its current fall sale , you can find domestic flights as low as $15. It's rare to see flight prices in the teens, so this is definitely a sale worth getting excited about.So where can you go? You can fly from Atlanta to Orlando for $15 and back for the same price. Air travel totaling $30 will leave you plenty to spend on tickets to Disney and fast passes galore. There are also over 30 flights costing just $20 — to exciting destinations such as New Orleans, Las Vegas, and Chicago.Most of the best deals included in this sale are for travel between October 17 and November 17, and to get the best offers, you should book by October 14. Availability varies by flight, so make sure to check out blackout dates and terms and conditions on Frontier's website before booking. Happy trails!