If you see something like this, buy it. My friend Lisa found this in some of her old stuff and knew that it was some sort of bar or culinary implement, but she didn't know exactly what it was. I instantly recognized it as an old-fashioned ice crusher and gladly took it in. The thing works wonderfully, in seconds pulverizing dozens of hard cubes into a finely crushed texture. I've seen them in antique stores all over, for cheap.
Crushed ice is a great thing to have around, especially as the weather turns warm and sunny. Make your own snow cone, or crush some ice to better shake a cocktail at home (it cools the drink down faster than big cubes from your freezer will), or use it for a great classic cocktail like the caipirinha.