Ultra Low Cost to FREE Airfares

I'm not what you'd call an international traveler, but there was no way I could keep quiet about this, even if I'll never grab these deals myself.
Frequently we'll see low-cost flights advertised and those rates can be impressive, but nothing that would fit into Cheap-2-FREE!, but some of the international carriers are really kicking it as Ultra Low Cost Carriers (ULCC).

Skybus a US based ULCC
Skybus started as a no frills carrier offering ala carte pricing. If you want a blanket in flight, you get one if you buy it, don't fret it's band spanking new. If you want a window seat, purchase priority boarding to get on the plane first. Their regular fares are approximately 65% less than other US carriers. Plus, there's 10 seats going for $10 on every flight!
Sign up for email notification to know when those seats are available.

Skybus operates at a lower cost by focusing on less busy airports and automating everything it can without sacrificing what passengers really need experienced pilots and new planes.

Spirit Airlines - Flights to the US, Caribbean and Latin America
Spirit Airlines is another leader in the ULCC. Offering a variety of flight specials including $19 one way (on website 2/25/08). Spirit Airlines flies to major US cities and offers special travel packages and cruises from their website.

You should sign up for email notifications for specials and to earn free travel.
They also offer a $9 Fare Club to get priority notification of specials so you don't have to fight thousands of others looking for a deal.

Ryanair a European ULCC
Between May 16th and 21st 2007, Ryanair held a 'sale' of 1 million seats at the low, low rate of FREE (100% free: no taxes or extra charges). More than four million people visited the Ryanair website within five hours. Don't miss out on their next "sale" join their special email list to find out about all specials and new routes.

Ryanair's CEO Michael O'Leary is working with the goal that eventually "more than half of our passengers will fly free." Ad revenues from tray-table and seatback ads, plus cash earned from major companies wanting to paint the exteriors of Ryanair's planes turning them into giant billboards will foot the rest of the bill. Now that fella's a thinker!

Wizz Air a Hungarian ULCC serving eastern Europe
Yes, it sounds like a name my friend Bubba would give an airline. Fortunately for you, these folks also know what they are doing. From the looks of the website they are frequently adding new routes. Sign up on this page to be kept informed of their ultra low specials. My source tells me they also have been known to give away free seats.

AirAsia (I think they're based in Malaysia)
AirAsia was introduced as a no-frills airline December 2001 and now have more than 48 destinations throughout Asia. No you won't get little hot towels or the beverage cart to make you feel special, but you will get airfares at 80% off their competitor's regular rates. AirAsia also works to provide the highest standards of safety while having a 92% on time rate as of 2/25/08 when I visited the site.

Their website does not give the option for America, so I used the Australian site to get the details in English. As seen in the ad to the right, AirAsia is also known for the freebie flights.
It looks like you need to sign up as a member from this Australian site to be kept informed of upcoming specials.

Now, should you get in on one of these Ultra Low to Free Fares, because I told you about it. Please feel free to pick me up a souvenier or send me a post card from your destination.