How about "any airline on which I can get a jumpseat to DFW or PHX on!"
Some days, it's America West, but last week it was American. Even put me up in first class, offered me warm pistachios and a chicken quesadilla! And let me put my bag into the front closet!
If I flew my own airline to work, well, my connection carrier, it would be a bag of pretzels, half a can of a "coke-type product" and a few minutes of a game of "Warcraft III" until the passenger in front of me reclines his seat and crushes my laptop monitor at an angle that I can't see the screen.
But in all seriousness, me and the Mrs non-revved on Alaska Airlines (ANC to SEA) back in May and they absolutely blew us away with their service in coach.
Friendly flight attendents that would work the crowd while boarding, the captain gave a fantastic predeparture brief over the PA, pointed out interesting facts about the terrain during the flight, the gate agents both in ANC and SEA totally took care of us.
I fly AA all the time....i really like the new seats b/c now when somebody reclines back you whole tray table doesnt move with it which was a hassle on the old seats b/c you drink might spill over...anyway...i have most of the time had excellent service out of them whether in first or coach....i mean..i have had male & female flightattendants who would just give you whole life to them & then you would have a few that were cocky & servicing u to much...as they are suppose to...i guess those are the ones who have bad days...hey...on AA ..if u get a male flightattendant then consider yourself lucky b/c they treat you the best...hey...some of the females do too..
Good service, friendly crews, on-time flights... most of the time. But I'm biased. So...
Anyway, other excellent carriers are... Delta, US Airways, AirTran, and like Doug said, Alaska, flew them from SNA to SEA roundtrip, probably the best flight I've ever been on, great people over there at Alaska.
I'm 6' 2". As much as I'd like to be loyal to any particular airline, it really gets down to legroom. I'd be willing to pay 20% more $$$ for 20% more room (although a cost analysis would tell you I should only have to pay 10% more for 20% more room).
Anyway, my most recent favorite was Northwest, because I was a frequent flyer and I frequently got upgraded.
oh MAN - i LOVED Alaska Air!!! they did such a great job with just pointing out scenic sights (i'll fly them again anyday and pay the buddy fare!!)... that's the whole reason i like to fly, besides the fact that we're defying gravity, of course!
How about Merpati's egg-beaters -- pretty cool / bizarre experience flying across Borneo with barefoot pilots slurping on noodles in - flight and the cockpit door flapping open and shut the whole time. Not to mention most of the passengers sucking on cloves, extinguishing them under foot on the cabin floor and praying . . .