#4 on Gene Marks' 8 Easy Ways to Become an Expert Traveler? Lose the rollerboard and get a TOM BIHN bag:
"Never, ever check luggage. It takes too long to retrieve and costs extra. Adapt, pack less, and buy a Tom Bihn bag. Why? It will fit anywhere, even under a seat when you're crammed into one of those little regional jets with smaller overhead space. And you can fit the universe inside."