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Baked potato soup (Cookinglight.com has a great one)
Potato pancakes
A thickener in other soups

I remember my mother once bought frozen twice-baked potatoes from a friend who was selling food products. Maybe you could try that? Scoop out the potato, mash it with grated cheese, sour cream, butter, salt and pepper, put it back into the potato, wrap it up in plastic wrap, freeze and re-heat it on a cold winter day.

Or you could do a twice baked potato casserole. This recipe uses ten baked potatoes. Maybe you could make something like that and freeze it? Note: I've never tried this recipe.

wow, that is a lot of taters!

Oven-fried potatoe skins (or deep fried)
Twice baked potatoes
Potato Dumplings
Skordalia
Homefries
Mashed potatoes (with cheese, herbs, bacon, etc)

Agreed with the other comments, and twice baked potatoes freeze quite well after filling, before the 2nd baking if you want to save them.

You could also make some mashed potatoes for shepherd's pie and freeze that for a make-ahead meal.

Gnocchi! It's surprisingly easy, and a lot of the prep time is cut out since they're already baked for you.

I recommend a frittata or a Spanish-style torta, as well. Dice up a little bacon or pancetta, then cook a little onion and garlic in some of the delicious rendered fat. Toss in the potatoes, and let it all heat, then pour in some beaten eggs (4 to 6 or so) seasoned however you like. Stir things around on the burner for a few minutes to make sure the eggs are setting up, then top with a little cheese and finish it in the oven at 350 degrees for 4-8 minutes.

Wrap in foil and freeze them they will baked back up nice if wrapped proper. Also baked potato salad is great stuff.

50? Donate to a local food bank.

HAAAAAAAAAAAAAAASH! Not Who hash (too early for a Dr. Seuss Grinch reference?) But corned beef hash!

boxty

Try cutting them up into different shapes and keeping them in the freezer. Instant hash browns, home fries, mashed potatoes... All the convenience without the preservatives. 50 potatoes. I'm kind of jealous actually.

I have never liked the flavor of baked potatoes held for a long period of time before serving. I would not invest more money by adding butter or cheese to try rescue these spuds. I have found you can only make twice baked potatoes from freshly baked potatoes that are still warm. Cold potatoes do not mash. At best, I vote for American or Homestyle fries or the frittata. For American Fries, heat a thin layer of oil in your favorite fry pan over high heat. Toss in the chunked potatoes (and some chopped onion, if you like) and do not disturb until brown. Stir once, add salt and pepper, then drain on paper towels. Serve with ketchup or your favorite dipping sauce.

I would not feel guilty if you need to toss the potatoes. If you consider the cost and extra calories of butter and cheese to try make these palatable, you are better off to throw them out.

creamy potato soup - i just had some leftover potatoes -- so i added a few quarts of homemade chix broth, and cooked them down a little, pureed with the wand, added fresh dill and half 'n half.... was pretty tasty ...
you could freeze that into portions..... stir a little cheddar in there, also.... soup season is upon us.

i see someone recommended potato dumplings. any recipes out there? my grandmother, who was czech (she always used to say her mother was "bohemian") used to make them and serve them with roasted pork studded with garlic, sauerkraut (that she made every fall and put up in mason jars then stewed with pork ribs), and brown gravy made from the pork drippings, and i regret never having learned how she made the dumplings. i've tried a few times, but it's always been a failure.

My grandma always uses leftover boiled or baked potatoes to make potato cakes. Scoop out the insides (you could chop up the skins too if they're soft) and mix with an egg or two and enough flour to make them hold their shape. Form into patties and fry in some sort of fat (bacon grease, lard, oil, or butter). Season with salt and pepper. Delicious!

Thinking out of the box...
-Salted Cod and Potato balls! (appetizer)
(mash potatoes, mix in flakes of salt cod add in a beaten egg, pepper, diced onions and chives. Roll into tiny balls coat with flour and fry.) Yummy!

-Potato and tuna casserole!
(figure it out as you go along!)

Enjoy!