I still like my Swiss Army Knife. It is lighter than some/most of the plier style multi-tools. Doesn't need it's on sheath like a fixed blade. Easy to pack in a pocket, or drop in a day pack, or other pack bag.
Oddly enough though, I find the mini versions to be the most useful. They have the knife blade, the scissors, and the tweezers, the items I use most often. Really handy for geocaching actually.
Not that the other knifes/tools don't have their place, but I have always liked my swiss army knives for their general purpose usefulness.