Come tomorrow, November 8th, many people (check the link for locations) will have the chance to see the inner most planet of our solar system make an attempt to eclipse the sun. This transit is a some what rare occurrence, as only about 13 will happen in the next 100 years. So grab your approved solar viewing gear and have at it!
SPACE.com — Viewer’s Guide: Watch Mercury Cross the Sun (warning, popups)
Wikipedia – Transit of Mercury