Gift giving is something of a fine art, and there are a lot of ways to get it wrong.
Even when you've known someone for a long time, and feel you have a fairly comprehensive model of his psyche, choosing something he'll like can be tricky. Of course, that's why nature produced the Amazon universal wish list and other such gift registries—For the long-distance relative who needs to just pick something, you can't do much better.
But the best gifts follow the desire/impractical measure, where the item is both A) something the person will want and B) something the person would never buy for himself.* If you can hit that target, you'll find the receiver in a particular state of joy, delighting in an item that for him represents true luxury.
Alternatively, you can also buy something incredibly weird, and send it with no explanation of what it's for, or why you chose it. Then you've provided on of the oldest gifts of them all, the gift of a new story.