Taca (a U.S. Airways partner) is offering some pretty cheap fares to Central America, but you've got to buy them through their website by tomorrow.

www.taca.com

Must travel during February and originate from LAX/SFO/IAH/DFW/MSY/JFK. Cheapest deals are out of IAH/DFW. Although terms & conditions indicate that no bonus ff miles can be earned on these fares, it appears you can get Dividend Miles credits.

For maximum miles (all destinations are the same price) head to PTY.