Here's a video that will cause everyone from chain smokers to secondhand "passive smokers" to shudder:

Still Smoking? Watch This !! - video powered by Metacafe

This video is of an experiment that was conducted in Oita, Japan to demonstrate just how much tar your lungs collect when you smoke.  400 cigarettes (or 20 packs) are unwrapped and one by one are burned in a process called the electrolization method.

The smoke from the cigarettes is drawn through a small bottle of water (the water acts much like your lungs) before the smoke is released into the air.  Note the color of the water as more and more tar is collected in it.

After the tar is extracted from the cigarettes into the water, the liquid is boiled in a process known as the vaporization method.  Take a look at what is left behind.

To point things in perspective:

If you smoke a pack of cigarettes a day, 7.2 grams of tar like that shown in the video is deposited in your lungs every 1.25 months.

If you smoke 5 cigarettes a day, this same amount of tar is deposited every 2 months.

If you smoke 2 cigarettes a day, this amount of tar is deposited in your lungs every 6.75 months.

If you are exposed to second hand smoke on a regular basis, it could take a year or more to have 7.2 grams of tar deposited in your lungs.  No matter how long it takes, would you honestly want a glob of sticky, chemical-laden tar in your lungs?

For more information of quitting and how to stay off nicotine for good, check out Determied to Quit.com.

If you live with a smoker and want to keep yourself healthy, consider how an air purifier like the IQAir CG MultiGas can spare your lungs from all that tar.