I found an even easier recipe for sardines than Alton Brown's avocado sandwich.
Ingredients: 1 can oil-packed sardines + 1 8-oz block of cream cheese
Procedure: Mash them together into a mostly uniform paste. Slather onto toast or use as a dip with crackers/pretzels. (Or just shovel it into your mouth.)
That's about it, though all kinds of minor seasonings can be added. (Some versions of this recipe drain the sardines first, but I don't.) I've been adding a tablespoon of red pepper paste (which pinks up the color from the undistinguished native beigey-grey) and a dash of lemon juice. Minced preserved lemon would probably be great, except that my big jar of preserved lemons is currently stranded at the back of the fridge behind leftover turkey.
Robustly flavored carby things (onion rye etc.) go better with it than blander ones. The spread mellows out the intense fishiness of sardines into a smooth, fluffy mouthful reminisent of cream cheese 'n lox-- come to think of it, poppyseed bagels might also work well, perhaps with an underlying slice of cheese to keep the spread from falling through the hole in the middle.