Roast potatoes, most definitely! Preheat oven, parboil potatoes, put goose fat in roasting dish, put dish in oven, when fat is reeeeally hot add potatoes and shake to rough up the edges. Put back in oven until crispy and lovely (and cooked), then sprinkle with sea salt and omnomnomnom.

not sure about timings for any of the above steps. I tend to eyeball.

Oh lordy yes, roasted potatoes. Alto's method sounds tasty, and I'll definitely try it myself. Here's mine: Preheat cookie sheet (jellyroll style--the one with sides) or roasting pan at about 425/450F. Melt fat so that it's liquid but not hot. While these things are happening, cut potatoes into whatever size & shape bits you want. Sprinkle with sea salt/kosher salt and pepper (I also sometimes add garlic powder or use some kind of seasoned salt), pour melted fat over potatoes, toss to coat. (I use my hands for the tossing, hence the not-too-hot fat.) Remove pan from oven & dump potatoes on it, spreading them out so that they're not touching, or at least not touching much. Roast for about 15 minutes, turn/flip/move around a bit (the side touching the pan will be crisping up), return to oven until done (time depends on size of pieces, but let's say 30-45 mins in total). These are BOP's favourite potatoes ever (and mine).

BOP thinks you could also use it to coat your body and swim in really really cold water, catching seals with your teeth.

When we were in Hungary, they would just spread it on a little toast round and eat it. I do not recommend that.