I got great use out of my Old Timer middleman jack for helping the kids open packages, but also ended up putting a few various SAKs and Leatherman multis (Wave, Micra AND a Squirt P4 LOL) into service at various times assembling stuff, putting in batteries, etc.
Funny story: Living here in Europe and being married to a Czech gal, our kids, who are 4 and 2, have the great advantage of getting some gifts on Christmas Eve from Jezisek (baby Jesus) and then a few more on Christmas morning from Santa Claus (ahh, the "burden" of having an American father). At any rate, this makes for some complicated planning on the part of my wife and I, making all this magic happen. At one point, I was trying to slip away to get down to our cellar -- which is accessed from the parking garage where we keep our car -- to get the presents from Jezisek. My daughter walked by the hallway where I was putting on my shoes to go out and asked me where I was going. Quick thinking on my part .......... "I have to go to the car, I can't find my knife," I said, patting my pocket, "and I think it fell out in the car." That satisfied her perfectly and she went about her business. So after all these many years of faithfully carrying one, it's still possible to find other uses for man's handiest too, the knife.
Later that evening, I'm happy to say, Jezisek made an appearance and brought the kids a wonderful bounty of goodies. Santa did a great job too.