Oneworld airlines have put East and West Coast USA cities to Europe on sale over the summer. For example, fly from New York to Milan, Italy for only $358 roundtrip
Error Fare, Business Class, summer, Christmas and New Year flights from many US cities to Port-au-Prince, Haiti for only $374 roundtrip with American Airlines.
Summer flights from Cincinnati, Ohio to Lyon or Paris, France from only $422 roundtrip with American Airlines and Iberia.
Very cheap flights from Atlanta, Minneapolis, Detroit or Cincinnati to many European cities from only $441 roundtrip with American Airlines.
Flights from Los Angeles to Cincinnati, Ohio for only $193 return with United Airlines. Also works in reverse.