Pan-fried, man ... it's the way to go. Reasonably thin slices, then crisp it way more than you think it needs ... to the point where it's more like bacon then like ... well ... spam. For full effect, to my way of thinking, it should be done over a campfire after a day of hiking, but that's getting fussy.
I really cannot conceive of eating the stuff straight out of the can, though I've heard that people do. I just ... geh. My imaginary taste buds rebel at even trying to form a taste-image.