I'm telling you, peanut butter is the universal sandwich ingredient. There are things that I'd never try putting on the same sandwich as peanut butter, maybe wouldn't even think of putting on a sandwich in the first place, but I'm sure the result is awesome anyway.
I would never think of combining fried egg and PB, and honestly it sounds pretty disgusting. But I bet it's great, just because apparently peanut butter and anything is great.
New challenge: Create a peanut butter and something sandwich which is not awesome. Only rule is that it must be a food that you actually like. No fair using something that's disgusting to begin with.