Spirit Airlines has service to Lima, Peru in South America and Cancun in North America. They also fly to San Jose, Costa Rica; San Pedro Sula, Honduras, Managua, Nicaragua and Guatemala City, Guatemala in Central America. I'm hoping for service to Panama City, Panama, but I'm not holding my breath.
I tried pricing a one-way flight to San Jose at the end of October. The final price was about $210, which really is pretty good. However, if the round-trip fare is double that, it is really kind of high.