Check out Spirit Airlines' $9 fare club. For $39.95 a year, you can access ridiculously inexpensive flights--even $2 fares. The airline flies to many major cities and a slew of locations in the Caribbean, Mexico, and South America. You'll receive e-mails every six weeks, listing cheap fares like the recent $17 one-way ticket from Fort Lauderdale to New York City. Passengers on the same ticket will also get member prices (as long as the member books).
Flickr photo by: Alaskan Dude