Who designed the original poster set with the black background and a picture with white text below?

I have seen those in offices, and I don't know who came up with them as far as the designer, but I'm almost certain that it was an ad agency. They're intended to be motivational posters, and they got to be ubiquitous for a while, as you pointed out. To me, they got to be a cliche, and I personally got TOTALLY sick of them. Apparently others felt the same way, because they came to be a bit of a joke.