Today Mercury will travel across the face of the sun, and at least part of the transit will be visible in various part of the North America and Hawaii, starting around 2:12 pm EST. However, according to NASA it will only appear as 1/194 the size of the sun and so a telescope would help immensely (some sort of eye protection is needed; see here for the safety measures you will need to take).
In Chinese metaphysics, the five naked-eye planets (Venus, Jupiter, Mercury, Mars, and Saturn) represent the five primary elements of the universe: metal, wood, water, fire, and earth, respectively.
See here for the NASA official site of the 2006 Transit of Mercury.
The Penciled Sky 