The Cheeky Monkey Pac Back has its good and bad points. This is a back pack frame that attaches to a regular carseat so that you can carry it on your back. We used this when we bought an airplane seat for our toddler and needed a car seat for her ride in on the airplane.
This is definitely better than dragging your car seat through the airport with nothing to help you carry it. It is convenient because it goes on and off the car seat very easily. You just kind of thread the straps through and you are ready to rock n roll. It's not big or bulky and could go into your luggage easily, too.
The negatives about this product are that it's very awkward to use. You are always smacking people with it, or rather attempting not to smack people with it. It's also quite uncomfortable. My husband is a broad guy, and he found it heavy and cumbersonme. Also when you are carrying it onto the airplane, you pretty much have to hold it up over your head, although I guess that's more the car seat than the pac back.
I haven't found a great solution to the problem of carrying a car seat through the airport, but this works okay.