With regard to alex.tan's remark:
"One weird custom is that on the first day of Chinese New Year, it is not auspicious to sweep the house. "

Some people believe that sweeping the floor on the first day of the Spring Festival would bring bad luck, as one would be sweeping all the good luck away from the house. However, there is another reason why sweeping the house is not encouraged.

The Chinese believe that everyone and everything deserved a rest on Chinese New Year's day, as most of the population would have been working hard around the year. The ancient Chinese did not have many public holidays like the modern world, so most businessmen would keep their shops open throughout the year. For Chinese women, who stayed at home to do the housework, every day would also be a workday. Chinese New Year was the only day in the whole year during which they could take a well-earned rest.

The ubiquitous household equipment like brooms, knives and the cooking stove are considered as living things as well. These pieces of equipment would be in service throughout the year, so the Chinese believe that they also deserve a rest during the first day of the Lunar New Year.

Therefore, no fires would be lit at the stove, no knives (or scissors) would be used and no floor would be swept during Chinese New Year. Food would be prepared the day before so as to give the women (and their equipment) a break.

p.s.: allseeingeye says re Chinese New Year: As a strange cultural flipflop to this, the Scottish believe it is bad luck to start the new year with a dirty house. We usually clean everything on the 31st! ;)
The Chinese also clean their houses on the last day of the New Year. In fact, they have a major clean-up of the house in the month leading up to New Year's. :)