Smashed Spuds (as I like to call them) usually have fat and milk added to them, as well as seasoning. Riced potatoes, on the other hand, are simply served as is, allowing the full flavor of the spud to come through. I have a ricer that's was sold as a Spatzle maker, and it works well for both appications.
Riced potatoes are elegant, and look very nice on the plate. If you've never served them as is, with just a dollop of butter on top, then you've cheated yourself.
You can also rice sweet spuds as well. It makes a great presentation. And If you ever get the urge to make pumpkin or winter-squash pie, after cooking the squash or pumpkin, run it through the ricer for silky smooth results.
I can't ever remember the name of the thing, but it is a conical collander, with a wire holder and comes with a pestle. You use the pestle to force soft foods, like potatoes, tomatoes, squash, etc. through the holes and into the bowl. This will also do a good job at ricing the potatoes, as will a hand cranked food mill, if you have one.
Back to the ricer, and then, there's always spaztle. Oh, and you can even use the thing to prepare potatoes for mashing
Seeeeya; Goodweed of the North