[OkayPhysicist]

For Spirit, a carry-on is considered an extra. That's an extra $35 right there, which brings it pretty much inline with Southwest's pricing.

[mdhen]

Get a big backpack, i got a tom bihn synik 30 that qualifies as a personal item. Let's me carry enough for any short trip without having to use a carry on.

[wddkcs]

They allow you up to two personal items/small bags.