1. A portable luggage scale
With all the extra fees airlines charge these days if your luggage weighs too much, one of these would be very handy. There are lots of different models, for example Travelon's Stop and Lock Luggage Scale and Samsonite's Electronic Scale.
Humangear's squeezable, silicone tubes hold lotions, shampoos, soaps, conditioners and the like on a trip, and would make a great gift for a traveling family. It's the extra features that really make these so cool: the no-drip opening, the rotating collar that makes it possible to label what's in each container, and the fact that they can be easily washed out and refilled.
3. Easy-to-pack travel games
Easy-to-pack games can be a mood-saver on long trips with kids. There are lots to choose from, for different ages and interests. Some ideas are the 6 in 1 Travel Magnetic Games, Melissa & Doug's Travel Memory Game, and the Mini-Puzzle Pack
4. Fun travel activities
Gifts that give kids something to do aboard airplanes and at airports are always welcome for traveling kids and parents. My own kids really like sticker books and coloring books and kits when we're traveling.
5. Wheeled backpacks
My kids love their wheeled backpacks (my son uses one at school too), and I think they make perfect hand luggage for children. There are many brands and models, for example JWorld's Kids's Rolling Backpack and GTMax' Rolling Wheel School Backpack.
6. A stylish & practical travel pouch or purse
A travel pouch or purse can make a great gift for parents traveling with kids. They're great for keeping the most essential items and documents like passports, money, and credit cards safe and close to your person. Pick a pouch that can be worn at all times so that it's less likely to be put down and forgotten in washrooms and restaurants. Some that I like the looks of are Travelon's Anti-Theft Messenger Bag and Everest's waist pack with lots of pockets and a cell phone holder.
7. Comfy neck pillows for adults and kids
Sleeping on-board an airplane will never be really comfy (at least not in Economy Class), but a neck pillow can help. There are lots of different ones to choose ones: memory foam, inflatables, kids' styles... A couple of nice ones are Travel Rest's "reinvented" travel pillow and Eagle Creek's Compact Comfort Travel Pillow.
8. A practical diaper backpack
This would make a great gift for any parent traveling with a baby or toddler. Two suggestions are DadGear's Backpack Diaper Bag and Baby Sherpa's Diaper Backpack.
9. Handy packing cubes
These cubes help keep your luggage organized, and can make a great gift for a parent who packs not just for themselves but for their children as well. One idea is to give some of the cubes to the kids to put their things in, and then just put all the cubes into a big suitcase together. There are lots of styles and brands, for example Samsonite's packing cubesand Rick Steves' packing cube set.
10. Some nice luggage tags
Anyone who travels needs luggage tags. Get some nice, colorful, big ones that can easily be spotted at the luggage carousel! And stick some on the hand luggage too, just to be sure. Two really nice sets of colorful tags are Bob's Your Uncle Schlep Luggage Tag Set and Initial It!'s Colorful Luggage Tag & Zipper Pull Set.
11. Some stylish travel clothing
Non-wrinkly, versatile, comfy, easy-wash-and-dry clothing: that's the kind of stuff I wish I'd get for Christmas! For example, I'd love the travel tunic, a pair of comfortable pants, or maybe some comfy slippers to wear on the plane.