There are many deities in Chinese folklore and mythology. One of which is 太歲爺, The Keeper of the Years. He's like a zookeeper for all the animals of the zodiac. Or at least, that's what we tell our five year olds.
I can't remember if He moves or the zodiac moves, but there is collision, thus causing "conflicts".
Each year, the dominant animal sign is In Conflict with The Keeper of the Years. This year, it's the Dog. Persons who were born in the year of the Dog (any year) are said to be In Conflict (犯太歲; Fàn Tài Suì) and, contrary to popular belief, this is not a lucky year for them.
If all the animal signs are placed in order in a circle, with the dominant sign at the 12 o'clock position, the signs at 3 o'clock, 6 o'clock and 9 o'clock are also In Conflict with The Keeper. This year, that would be the Ram, the Dragon and the Ox.
It's as big a deal as you make it.
Those who are In Conflict in any particular year might go to a local temple and get 安太歲 (Ān Tài Suì; The Appeasement) done, any time between the first and the fifteenth day of the Lunar New Year (you have until February 12, 2006). You give them your full name and a donation, they take care of the rest. In some places, the donation is a set amount that can be used as a tax credit. In some temples, it's whatever you want to give. In some places, it's free. Do as the Romans do.
Some will just keep auspicious guardian signs around them (stuffed animals, wall posters, jade charms, etc.). For the Dog, keep the Tiger and Horse close by; for the Ram - the Rabbit and the Pig; for the Dragon - the Rat and the Monkey; for the Ox - the Snake or the Rooster. Jade charms may be available for sale at temples that do The Appeasement.
Most commonly, those In Conflict just take extra care to be cautious this year. Watch your step, tie your shoelaces extra tightly, hold on to railings when going up and down flights of stairs, floss, wear sunscreen, make better food choices, start or keep up with the good exercise habits, refrain from making risky investments, opt for that extra bit of insurance coverage, do not vacation in Iraq... that sort of thing.