I do not remember where I found this recipe, but it is very simple and super fast. I used it with sword fish steak, but I am sure you can use it on any other fish as well. This is what I did:
Combine 1/2 lemon juice, 1 tbsp olive oil, 1/2 tbsp mint, 1/2 oregano, 1 glove crushed garlic in a dish. Coat your fish steak with the mixture and throw on the grill (I used the George Foreman grill). Spoon more mixture on top. Grill for about 6-8 minutes. Devour.