The annual prizes, meant to entertain and encourage scientific research, are awarded by the Journal of Improbable Research as a whimsical counterpart to the Nobel Prizes, which will be announced next week.
Ig Nobels also went to researchers who found that the male buprestid beetle likes to copulate with Australian beer bottles called stubbies, and researchers who showed why discus throwers become dizzy and hammer throwers do not.
Former winners of the real Nobel prizes hand out the prizes at a ceremony held at Harvard University in Massachusetts.
A personal favorite of Marc Abrahams, editor of the Annals and architect of the Ig Nobels, is this year's winner for the Public Safety Prize, which went to John Senders of the University of Toronto, Canada.
Senders and colleagues conducted experiments to see how distractions -- in this case a helmet with a visor that repeatedly flaps over a person's face -- affects attention during highway driving.
"They put this on someone while this visor is flapping and blinding them," Abrahams said.
Remarkably, the driver fared quite well, Abrahams said.
Peter Snyder, a professor of Neurology at Brown University in Providence, Rhode Island, was part of two research teams who won the Medicine Prize for studying how the urge to urinate affects decision-making.
Snyder's team set up an experiment in which volunteers did computer tests and then periodically drank 250 ml (about 8 ounces) of water as the scientists measured the effects of the volunteers' gradually swelling bladders on attention and working memory. The aim was to see who could last the longest before bolting for the toilet.
The study found that attention and working memory suffer when you are so focused on having to pee.
"When you gotta go, you gotta go," Snyder said.
Abrahams said Ig Nobel judges spend much of the year sifting through piles of nominations, and the selection process can become quite heated.
"We have a devil of a time picking them. I have to step in and remind them what prize it is we are arguing about."
-- Arturas Zuokas, the mayor of Vilnius, Lithuania, winner of the Peace Prize for showing that the problem of illegally parked luxury cars can be solved by running them over with an armored tank.
-- John Perry of Stanford University for his Theory of Structured Procrastination, which holds procrastinators can be motivated to do important things as long as they are doing them as a way of avoiding something even more important.
-- Anna Wilkinson of the University of Lincoln in the United Kingdom, Natalie Sebanz of Radboud University Nijmegen in the Netherlands and others for their study that found no evidence of contagious yawning in red-footed turtles.
-- Makoto Imai, Naoki Urushihata, Hideki Tanemura, Yukinobu Tajima, Hideaki Goto, Koichiro Mizoguchi and Junichi Murakami of Japan for determining the ideal density of airborne wasabi -- a pungent horseradish -- to awaken sleeping people and for applying this knowledge to invent a wasabi fire alarm.
-- Karl Halvor Teigen of the University of Oslo, Norway, for trying to understand why, in everyday life, people sigh.
-- Americans Dorothy Martin who predicted the world would end in 1954; Pat Robertson who predicted the world would end in 1982; Elizabeth Clare Prophet who predicted the world would end in 1990; and Harold Camping who predicted the world would end on September 6, 1994, and on October 21, 2011; Lee Jang Rim of Korea who predicted the world would end in 1992; Shoko Asahara of Japan who predicted the world would end in 1997; Credonia Mwerinde of Uganda who predicted the world would end in 1999 -- for teaching the world to be careful when making mathematical assumptions and calculations.