Until today, Portfolio.com’s Felix Salmon had no idea that there was a mega-billion dollar eye care company called Alcon — but when he pulls out his calculator he comes up with some interesting numbers:

“On a valuation level, let’s say that the population of the world is 6.6 billion, and let’s exclude the ‘bottom billion’ for the time being as people who are never going to avail themselves of Alcon’s products. That leaves 5.5 billion people, with 11 billion eyeballs between them. Which would mean that Alcon is valued at over $4 per global eyeball. Nice.”

For the record, Reuters reports that Novartis is buying Nestle’s 77 percent stake in Alcon for $39 billion — $11 billion up front, and $28 billion between January 2010 and July 2011 — which would imply a $50.64 billion total valuation, rather than the $45 billion figure Salmon uses.

The deal cost Novartis its triple-A credit rating, and loaded up Nestle’s acquisition war chest.

(Photo:  Reuters/Hong Kong movie star Jackie Chan plays with fake eyeball)