Smartwool has so many wonderful holiday gift options for all ages. Even a pair of their colorful socks would make an excellent gift or stocking stuffer, there are so many great things to choose from, and their products scream quality. I love their stuff especially for outdoorsy types because wool is the ultimate choice for travel and outdoor activity, keeping you comfortable by regulating body temps.
Check out their Diamond Popcorn Scarf and matching Hat. I am madly in love with the Polar Purple, which is a soothing periwinkle purple-blue. I don't see it on their site at the moment, but a quick google search shows you where to find it. It's two-toned and looks great and comes in other colors, even basic black.
This would be a fabulous set for the person you're not quite sure what to give. You can find Smartwool online or locally at shops like REI, and food co-ops (it doesn't get easier than picking up a gift while you're grabbing groceries).