The hookah: it's not just for weed anymore. Actually, it never really was. The hookah is a staple of life in pretty much every end of the Muslim world, and it has been for a really, really long time now. The normal combustible of choice is not marijuana, even though that is the first thing we barbaric Americans think of when we see one, but rather flavored, molasses dipped tobacco, which most Arab speakers refer to as shisha.
When smoked, shisha smells more like an exotic perfume than any smell normally associated with cigarettes or even pipe tobacco. The taste is likewise quite mild and pleasant, as well as being cooled by the water. Shisha is usually flavored with fruit extract and comes in many flavors, including apple, which is the most common, plain molasses, pear, mint, jasmine, cherry, and many more. While it's not necessary to inhale while smoking shisha, and I know many who do just smoke it for the taste, but if you do inhale the smoke, you can develop quite a pleasant and relaxing little nicotine buzz rather quickly, even if you're a regular cigarette smoker. One bowl of shisha shared among three or four friends will last as long as an hour, and makes for quite a fine way to wile away part of a lazy afternoon.
Because the use of alcohol is forbidden to observant Muslims, smoking hookahs has taken its place in many ways; after a good meal, instead of after-dinner drinks, you break out the hookah. There's even a sort of bar culture revolving around hookah bars. I spent most of my senior year of high school in a hookah bar in one of the Arab parts of the DC suburbs, one of three or four white kids in a room full of old Arab men playing backgammon, and it's an experience I wouldn't trade for all the hours of class I skipped.
Because the tobacco is filtered through water in a hookah, many of the harmful carcinogenic chemicals are filtered out, though it's still quite possible to die of lung cancer from a lifetime of smoking hookahs.
As a final note to the incorrigibly illegally inclined, the idea of putting whole marijuana buds in a hookah would make you seem quite gauche to an Arab. The preferred method for using a hookah as a mind-altering device in the middle east is to sprinkle hashish or opium onto a bowl of shisha.