You know, if government forced airlines to pass on the savings from drastically increasing passenger loads, I'd be perfectly happy to stand up for a dirt cheap flight.
Jet fare is ridiculous, especially in North America. And I suspect that increasing fuel prices are going to be a huge problem in the future, because present jet engine design is based around kerosene fuels. Ironically, conceptually jets are very flexible on fuel (the designer said they'd run on peanut butter) but in practice we've built this elaborate technology around something similar to lamp kerosene, for civilian aircraft at least.
As unappealing (on many levels) as a sardine-can flight would be, if it led to a 30-50% price drop I'd leap at the option. Well, probably hop awkwardly since my legs would be shot.