Transits of Mercury and Venus don't happen as often. The next one for Mercury is in 2019. Venus had a pair of transits in 2004 and 2012 but the next one won't happen until 2117. I hope to be able to retire by then and have time to watch it. Maybe someday soon colonists on Mars will be able to see an Earth transit.
Mercury is the smallest and innermost of the solar systems eight planets. Remember that Pluto has been demoted and a distant ninth planet has been theorized but not yet found. Mercury orbits the Sun every 88 days while its "day" is 59 Earth days long. The surface of Mercury looks remarkably like our Moon. It's off white and heavily cratered with the side facing the Sun searingly hot and the dark side frigid.
Obviously you NEVER look directly at the Sun. To see the transit you will need a properly filtered telescope - something most of us don't have. Alternately, you could try to project an image of the Sun and the tiny black dot of Mercury thru binoculars onto a sheet of white paper. If nothing else, you may set the paper ablaze! Probably the best option is to view the transit online at NASA's website. That should make both your ophthalmologist and the local fire department happy.
~ For another way to view the transit check here.
~ Check out a video of the transit from NASA here.