If it is a good sturdy type fillet, try cutting it up into little chunks and pan frying it in some butter and garlic. Then, take some fresh corn tortillas and heat them in some oil (olive oil works.) chop up some avocado, onions, tomatoes and cilantro. Throw the fish pieces in the tortillas, top with the chopped up veggies. Make a sauce by mixing some paprika and ranch sauce and pour into each tortilla or serve on the side. Voila, fish tacos.
I haven't actually tried this, but we just inherited a massive amount of striped bass from my father's recent fishing trip and I plan on trying that this weekend. It seems like the closest thing to my all time favorite fish tacos, served at Tequila's in Golden. (You know it, HLJ.)