One of those fad OTC herbally things that are supposed to "cure" the flu.
Here you go:
"Oscillococcinum's active ingredient is Anas barbariae hepatis et cordis extractum 200CK, made from the heart and liver of wild duck and is diluted repeatedly until essentially no molecules of duck heart or liver are found in the actual pill. It is thought that because wildfowl are a natural resorvoir for influenza and nucleic and phosphoric compounds in the pill resemble influenza, that the combination contribute to antiviral activity, but the exact mechansim of action is not well described. "
and
"Oscillococcinum (or Oscillo[1][2]) is a homeopathic preparation marketed to relieve influenza-like symptoms. It does not provide any benefit beyond that of sugar pills. It is a popular preparation, particularly in France. It is manufactured by Boiron, its sole manufacturer. Oscillococcinum is used in more than 50 countries and has been in production for over 65 years.
The preparation is derived from duck liver and heart, diluted to 200C—a ratio of one part duck offal to 10400 parts water.[3] Homeopaths claim that the molecules leave an "imprint" in the dilution that causes a healing effect on the body, although there is no evidence that supports this mechanism or efficacy beyond placebo.[4][5][6]
Oscillococcinum was originally proposed by the French physician Joseph Roy, based on his misidentification of an oscillating bacterium he named oscillococcus in victims of the Spanish flu epidemic of 1917-1918. Roy said he had seen the same bacterium in cancer sufferers, and proposed a homeopathic preparation (which he claimed to have isolated in a duck) as a remedy for the Spanish flu. The microbes Roy said he saw have never been independently observed by any other researcher. In addition, it is now known that influenza is caused by a virus and not a bacterium."
It's always wise to beware when some crackpot tries to sell you snake oil. ;~)