solving the rubik's cube, best puzzle ever, as fast as possible. It is very entertaining to solve, especially when you can solve it in under 30 seconds. It is a very physically demanding sport. You need to have very fast fingers and reaction speeds. It is very much like track and field.
speedcubing.com has list of cube records.World record so far is 9.77 seconds by Erik Akk
Speedcubing is the hobby of solving the Rubik's cube incredibly fast (eg. 30 seconds or faster). A person who practises speedcubing may be known as a speedcuber.
Even after the official competition had finished, the competitors couldn't stop speedcubing.