:[http://allegiantair.com Allegiant Air]
:[http://frontierairlines.com Frontier Airlines]
Look online for more!
use airhitch or a like program. Airhitch gets you across the Atlantic for under $300, though you have to be flexible. Basically fills the role of what used to be standby for flights (although airline worker family members can still fly standby, but for a bit cheaper).
for airhitch are not very positive, but some claim to have done it .