February 3 in Japan is Setsubun. While the word setsubun literally means "seasonal division," it normally refers to the divide between winter and spring, according to the lunar calendar. Traditionally this would have been the new year, and so the celebration of Setsubun is related to chasing away the evils of the previous year and inviting in good for the year to come. A sort of spiritual spring cleaning. The evils are physical evil spirits, represented as red-skinned horned devils.
The human defense against these evil spirits?
Soy beans! This time of year they are sold in sets, often with masks so that people can pretend to be the evil spirit (being scared out of the house) and the good spirit (being welcomed in).
Thus properly attired, people will throw the beans around the house and out of windows and doors. As they throw they recite "oni wa soto, fuku wa uchi," which means "devils go out, good luck come in!"
Then each person is supposed to eat the number of beans (not ones that have been thrown about the house) that corresponds to their age.
My Japanese friends are always surprised when I tell them that I too throw beans about my apartment and eat the requisite number. They find my following Japanese traditions amusing, but I figure I can use all the good luck I can get! Although I must admit to throwing my beans strategically - one year I got a little carried away and was still finding beans under the bed and in hidden corners for months!
For those of you who aren't in Japan but want to participate anyways, try your hand at this online game!