File under: You gotta be kidding me. Starting May 5, you'll have to pay an extra $25 to check a second piece of luggage on United Airlines. Unless there's rioting on the jetway, expect other airlines to follow suit. They always do.

United says the change will generate $100 million in revenue and cost savings a year... and it will probably cause untold havoc on actual planes, too. Why? Because all those people that would normally check a second bag will probably try to carry them on instead of paying the 25 dollar fee, and that will mean longer lines at security, less room in those already jam-packed overhead bins, and more of those people wandering up and down the cabin at takeoff time trying to find room for their bags at the last minute... only to have them gate checked at the last minute. Will those bags cost an extra $25, I wonder? Will the flight attendents collect the money? And will they prefer exact change as they do for that terrible mini bottle of white wine? But hey, it'll save United a couple of bucks, so let's all give 'em a hand.

Premier customers, international travelers, and anyone traveling in a pricier part of the plane will have the fee waived.

While I understand the airlines need to make money in an era of $4 gas, I can't help but feel like nickel and diming passengers isn't the way to do it. Southwest charges more to let you get on the plane first. And some airlines are even talking about charging for an assigned seat. On Northwest you pay extra to ride in the exit row.

Why not just raise prices modestly across the board and leave services the way they've been? Oh, right, because if you don't have the absolute "lowest fare," no one will ride on your plane. Meh.

LINK: United to start charging for second bag