
"All of this started with a simple observation. Chaffer was looking at a flask full of human breast cells and noticed that a small [number] of them were floating, rather than stuck to the bottom. She says, “Normally when we see floating cells in tissue culture, they are dead or dying. However, in this case, I noticed that they maintained a healthy appearance.”
The article goes on to explain the discovery and some implications, but I just love that her recognition of something odd that's probably happened many times in many places turned into what could be a major advance.
via blogs.discovermagazine.com