If you live in/near a city that Southwest Airlines serves, you can fly to Cabo on Southwest/Airtran.
Look up the combo 2 X 50,000 point Southwest Chase credit card offer -- in short, if you can get it done in time for your trip, you end up earning 106,000 points (50K for each card, plus 3K min spend per card); if you spend another 4K (total of 110K points), you then qualify for Southwest's companion pass, which means free travel for your companion for (a) the remainder of the calendar year in which the pass is issued, and (b) for the entire next calendar year. Try to time this so that the companion pass is generated early in a calendar year, so that you end up with a companion pass for as close to 2 full years as possible.