I recently flew on Allegiant, twice. Well, I guess four times, when you consider it was two roundtrips. <img src="http://www.traveltalkonline.com/forums/images/graemlins/Grin.gif" alt="" />

Allegiant charges for literally everything also. They kind of suck you in with a low fare and then charge for everything, including taking credit cards! <img src="http://www.traveltalkonline.com/forums/images/graemlins/duh.gif" alt="" /> They were actually pretty organized and ANAL about carry on bags. If you wanted to take a carry on bag that didn't fit under the seat, you had to pay for it, and your boarding pass was noted that you paid for a carry on bag. AND when you boarded, those who paid for a carry on bag had a lower boarding number than those who didn't pay for a carry on. The overheads were only about half full on fully booked flights, all four legs, and the plane boarded and deplaned in fairly record time.

...which is not to say that I necessarily am in favor of this BS of charging for everything, but that was my experience. Allegiant has a lot of other problems, in terms of delays, cancelled flights, etc. But their model on baggage seems to work..