In The Incredible Hulk (2008), Stan Lee's cameo is more related to the plot than his other cameos. There a scene where Bruce hurts himself in the factory and spills some blood, he freaks out and stops the production line to inspect the bottles. He cleans up some blood from the conveyor belt, but a dramatic camera pan shows the audience that some of it ended up in a bottle. Next thing is Stan Lee's cameo where he drinks from that bottle (are we even sure it's the same one? It's only implied I think) and he collapses. There some news story in the background in a later scene about it, but that's all we get.
It seems weird, was the only point of the factory scene to set up a 15 second cameo? I feel like there's some significance I'm missing, maybe it's a reference to something in the comics? A deleted scene that goes more into this?
His other cameos are really just that, simple cameos, but this one is related to the plot. I was really wondering the whole movie what would happen with that old man who drank the Hulk's blood, but I got nothing...