The 2009 Ig Nobel winners, awarded Thursday at Harvard University by the Annals of Improbable Research magazine:
VETERINARY MEDICINE: Catherine Douglas and Peter Rowlinson for showing that cows with names give more milk than unnamed cows.
PEACE: Stephan Bolliger, Steffen Ross, Lars Oesterhelweg, Michael Thali and Beat Kneubuehl for investigating whether it is better to be struck over the head with a full beer bottle or with an empty beer bottle.
ECONOMICS: Executives of four Icelandic banks for showing how tiny banks can become huge banks, and then become tiny banks again.
CHEMISTRY: Javier Morales, Miguel Apatiga and Victor Castano for creating diamonds out of tequila.
MEDICINE: Donald Unger for cracking just the knuckles on his left hand for 60 years to see if knuckle cracking contributes to arthritis.
PHYSICS: Katherine Whitcome, Liza Shapiro and Daniel Lieberman for figuring out why pregnant women don't tip over.
LITERATURE: The Irish national police for issuing 50 tickets to one Prawo Jazdy, which in Polish means "driver's license."
PUBLIC HEALTH: Elena Bodnar, Raphael Lee and Sandra Marijan for inventing a brassiere than can be converted into a pair of gas masks.
MATHEMATICS: Gideon Gono and the Zimbabwean Reserve Bank for printing bank notes in denominations from 1 cent, to $100 trillion.
BIOLOGY: Fumiaki Taguchi, Song Guofu and Zhang Guanglei for demonstrating that bacteria in panda poop can help reduce kitchen waste by 90 percent.
Source: Annals of Improbable Research.