Many New Year's Eve revelers in Denmark traditionally smash old plates against friends' and neighbors' doors.
The custom is associated with good luck and friendship. A large pile of broken crockery outside a home is traditionally interpreted as evidence that the household has many loyal friends willing to visit and celebrate. People may save unwanted plates throughout the year for this purpose.
The tradition is often described alongside other Danish New Year's customs, including jumping from a chair or sofa at midnight to symbolically leap into the new year. Fireworks, festive meals, and the televised royal New Year's address are also important parts of the Danish holiday.
The plate-smashing practice is not universal, and modern households may observe it less often than earlier generations. It is also different from ordinary accidental breakage: the deliberate noise and the resulting doorstep pile are the symbolic elements.