A hard surfacing material such as Borium (tungsten carbide) can be applied at the toe and/or heel of the horse's regular steel or aluminum shoes in smears, beads or points. A torch or forge is used to melt the carrier metal and adhere carbide grit or chips of various sizes to the shoe surface. Borium works best when used at a 1/8" to 1/4" thickness on the shoe.
It doesn't have to be as much as is shown in that picture though. My farrier just puts a little nugget of melted metal on either side of the heal end of the shoe, about the size of a pea. It just gives them some traction. But it will cut up a horse if kicked, so usually barns only allow it on the front.
And snow pads too. There are different types, one is a thin rim of rubber that goes around the edge of the shoe but my preference is the solid black pad with the ball in it to prevent snow/ice build up. With the complete pad, you don't have to pick out feet, which I appreciate.
I have heard of the grease as well, a lady here used to do it and it helps!
I ride in the snow all the time! Our horses are barefoot here so I don't worry about snowballing, but I always bring a hoof pick with me just incase.
I do a lot of trail riding in the snow as we don't have a ring, being very cautious and paying attention is the biggest thing, I've gotten used to the trails now, and know where the ice is and I stick to the trails that I only know. In our field I jog where I feel comfortable and that's about it! It's hard keeping warm at a walk when its -30 or -40 out though lol, bundle up!