Hand crank meat grinder, other uses?

Just keep thinking about it and opportunities will suggest themselves:
calves' liver to make patties or a rough pate;
harder fruits for making sauces and preserves (apple, pear, quince);
raw ingredients for cranberry sauce (the berries, whole orange, some nuts and spices).

I am not familiar with that particular brand. Generally, I used electric meat grinder like this http://pro-meat-grinder.com/best-product-reviews/, instead of a hand crank or manual meat grinder. Many people use a manual grinding device, this is very odd purchase. The hand crank meat grinder is smaller than an electric grinder. An electric meat grinder can grind meat much faster and more efficiently than a hand crank grinder.
Sometimes people use this hand crank grinding device for making guacamole. You could use it for grinding softer nuts. Also, they are pretty good for chopping onions.

Mincemeat. Old recipes for home made mincemeat with plenty of brandy and suet (the suet has to be chopped by hand but the beef can be ground in the meat grinder) are delicious.

I am not familiar with the brand you mentioned, but both my mother and grandmother had meat grinders when I was growing up. They looked something like the one puctured here: http://www.google.com/search?q=meat+grinder&ie=UTF-8&oe=UTF-8&hl=en&client=safari#biv=i|0;d|wipoWRaEU5jubM:

The grinder had different plates which were used for grinding various ingredients. We made a traditional stuffed noodle dish every year for Maundy Thursday and the grinder dispatched with the meat, onion, parsley and other herbs, and spinach. At Christmas, Mom used the grinder for chopping up candied fruits for fruitcake and nuts for cookies.

The grinder came apart--the handle was held on by a large screw. When that was unscrewed, the whole grinder could be broken down and washed, so there was no reason to keep it dedicated only to meats.

If you do have a sausage attachment, try to have a helper if you stuff sausage into casings--one person turns the grinder handle and the other person catches the encased sausage as it emerges from the machine.

I re-read your question about how it relates to grains. Yes, I think it could be used for grains to make veggie sausage and patties for burgers. With cooked rice, oats..mushrooms, herbs, spices, etc. And some vegan binder added. (maybe agar?). I'd look up vegetarian sausage and patty recipes and see what you come up with and use those as a departure point.

Does it have a sausage maker attachment available..if so you could stuff your own sausages.
Or just grind up pork spices etc to make sausage patties (and freeze them if you're making a big batch).

You could also experiment with making some more difficult to find sausage--Italian, for pizza. (okay not to difficult to find). Spanish Vs Mexican Chirozo. (sometimes hard to find Spanish which is more paprika and less hot than Mexican).

And Boudin sausage for New Orleans dishes--which sometimes hard to find. Look for recipes that include liver--pork liver can be hard to find, use chicken liver and pork; cooked rice, green onions, Cayenne pepper, onions, parsley--etc..etc). Great in "Dirty Rice".

And maybe look into getting curing salts and casings to cure the susages..and low smoke them, or just make 'sausage patties' as mentioned. as a dry run test project.

I'll grind (with a mini prep) some pork and crushed fennel, thyme, oregano, red pepper flakes, garlic, a touch of Morton's 'tender quick" and let them sit in the 'fridge overnight for Italian sausage for pizza.

We used to have one when I was a kid,but it was too heavy and we got rid of it.My mom used it to make kibe,wich is like an arab meatloaf with bulgar weat and onions.They all went in at the same time and it was easier to mix everything that way,so I guess you could use it to make meatballs,or your own sausage,meatloaf or kibe,and I don't see any harm if you use it for egg salad,or mashed potatoes,or for hard cheeses to go on pizza when you don't need them to be finely grated,if you clean it well.Use hot water and soap and I think it will be fine,but I don't think it would work on grains anyway.

Unless you have a grinding die (?) that will grind that finely, I don't think it will work for grains or nut meal. And that whole cross contamination thing makes me a little leery of using it for anything other than meat.

You could, however, use it to crush tomatoes.