Today is the day before spring begins according to the lunisolar calendar. On February 3rd, the Japanese celebrate Setsubun, celebrating the start of spring. Setsubun no Hi (節分の日), also known as the Bean-Throwing Festival, celebrates the start of a new year according to the lunar calendar. So several things are done to bring good luck to the coming year, as well as chase away the demons of the old year.
First, is the ritual of mamemaki (節分), which literally translates as bean-throwing, to drive away bad luck and demons (called oni). Usually someone in the family will dress up as a oni and people will stand at the doorway and throw soybeans at the door until the oni retreats. We had way too much fun throwing soybeans at Oni-Tiara, who in turn had way too much fun eating the soybeans.
So now that you've driven out the bad luck and oni (and in our case, attracted a begging pooch), you now eat some soybeans yourself to invite good luck in. Traditionally you eat as many soybeans as your age (Tiara should have stopped at seven beans) but I ended up snacking on them while I wrote this post, so I'm either extra lucky, or more probably, just fatter.

Another ritual is eating ehomaki, a makizuki sushi roll that is completely uncut, and contains 7 different ingredients for good luck. You're supposed to eat it in complete silence while facing a special auspicious direction that changes every year, for instance 2014 the lucky direction is east-northeast.
Now, even if you don't want to eat a whole sushi roll in complete silence, ehomaki are very tasty! They are actually just uncut futomaki, or fat sushi rolls, but it is kinda fun to eat them uncut like a giant sushi burrito. Maki-san at JustHungry has some great ideas for nontraditional ehomaki fillings on this
page, as well as the most traditional fillings.