I like fish in forms that most people would turn their noses up at. I like anchovies, sardines and pickled herring. I grew up eating most of these items and still enjoy them as an adult. I didn't have anchovies until I was an adult, but love them. I know that most people hate them, though, so I only eat them when I'm home alone. That means I don't get to enjoy them as often as I would like, which only increases my enjoyment on the occasions when I do eat them. They're like rare treats. Most of them are also healthful foods.
Sardines area also relatively healthy and totally natural. Other than cooking and cleaning the fish, a can of sardines is a whole food. One $1.50 can of sardines provides 19 grams of protein and 25% of the RDA of calcium. It is a bit high on cholesterol, though. I don't eat many animal-derived foods, so I don't worry about the occasional can of sardines causing too much damage. Tuna has a touch more protein, with less fat & cholesterol, but also less calcium. I do eat tuna as a diet staple, so sardines are a nice change of pace.
I love pickled herring. Only in wine, not in sour cream. Maybe it's because I love almost anything pickled. Give me pickles, pickled okra, pickled eggs and pickled spicy garden mix and I'm a happy eater. I won't eat pickled pork hocks, though. Did when I was a little kid, before I realized a hock is a pig ankle. Yuck. Pickled herring is a bit more processed than sardines, so there is sodium and sugar added, which makes it taste good, but adds calories. It's also pickled, so I can only eat a small amount at a time. A normal serving size is about 100 calories. Online searches will show more calories, but they suggest a portion of one whole cup. That's a bit much for me.
I also love anchovies. Could eat them on pizza and salad every time. An entire 2 ounce can of anchovies is under 100 calories. I can't imagine eating an entire can, unless it was on top of a HUGE pizza. That same can has 13 grams of protein, omega 3 fats and a TON of sodium. The sodium is one of the reasons I love anchovies, but also a good reason to eat them sparingly.
I know many of you stopped reading well before this because you find all of these forms of fish to be disgusting. I hope that I may have changed your mind and convinced you that they can be a great way to get protein into your diet. If not, I'll keep eating them on my own when no one is around.