For example, for very active people, mountain climbing is a form of meditation. It forces them to be very conscious and aware of the present moment. Straying off into the past or future could have very bad consequences. To others, the peaceful, methodical activity of washing dishes or walking their dogs brings them the contentment sought through other forms of meditation.
Eventually, everything becomes meditation as your inner and outer life become integrated. You can be working at the Xerox machine and still maintain a sense of contemplation and serenity.