For years my DH and I have kept "wish folders." We will print out an image of what we want from Amazon or from newspaper ads, etc. and put them in our respective folders. We do this year-round and occasionally will take a few minutes to "prioritize" the things we would like to have. When a gift-giving occasion comes up, we don't have to ask each other what we want; we just go to each others' folders. It's still a surprise because we don't know which gift(s) the other picked to give, and we still get things that we know we'll like.
That's not to say that we never buy each other things that aren't in the folder, but if we are stuck and can't think of anything we have that as a resource.