Southwest Airlines has launched a $39/one way "short haul" sale good for travel thru May 25, 2010. From the Bay Area, short haul flights include all Southwest-served cities in Southern California and Nevada. For example, a flight between Oakland and Las Vegas is just $99/roundtrip, after all taxes and fees. Among the rules: Fare not available on Fridays or Sundays; tickets must be purchased by February 11th for these reduced prices.
Click here for more information.
Other airlines may match these discounted rates in certain markets.
So shop around!