Bong Materials
Plastic:
Obviously the most common of bong materials, plastic is a versatile, light, and almost unbreakable substance with which one can make a good bong. It cuts easily, melts easily, holds water very well, and is highly receptive to the use of hot-melt glue and silicon (for sealing the stem/body abuttment). Plastic is also one of the two materials bongs are made of that can be transparent - useful for determining when that sucker needs a cleaning or new spooge! Many plastic bongs can be purchased commercially, and are the most cost effective purchase for the lazy or uncreative stoner.
Glass:
Many hard-core bongheads swear by glass, and with just cause! Glass has remarkable temperature conductivity! It has a tendancy to keep that water cool and crisp for longer than most other materials. It also feels nice up against your lips; feels more natural than the other options. A little on the heavy side, but this is a blessing - the thicker the glass, the more thermous-action for that spooge! These bongs are generally left in the bedroom or living room, as they are not only cumbersome, but highly BREAKABLE! Definately not the choice for stoners with friends that get clumsy when on the weed!
Ceramic:
Ceramic bongs have all the same benefits of a glass bong, minus the transparency. They are also slightly less brittle than glass, so a safer bet than glass for the traveller (or those clumsy friends) if you favor the feel and conductivity of earthware in a bong. This material is also within most people's means of production, whereas glass-work is generally a skilled trade. Sure, there's some skill involved in glazing and firing a good piece of clay, but blowing glass is a truly involved process, and not something I'd suggest trying without a good $5000 investment in the proper equipment.
Metals:
This is the area where I have the most experience in production, and can fully attest to the value of a well manufactured stainless steel or titanium bong! Both of these materials have even higher temperature conductivity than glass, lighter (in the case of titanium), and are of course far less brittle than all other bong materials. You'll pay alot for these bongs, and the cost can be prohibitive, but I'd suggest making one to anybody with the proper means. Titanium is indubitably the best material I have ever smoked from! When you place a titanium bong in a freezer for 45 minutes, remove, fill it with ice, and smoke up.... you'll swear no smoke is hitting those lungs of yours - until you exhale! It is also a fully hypo-allergenic metal, which cannot be said for brass, bronze, copper, steel or aluminum.
Wood:
I've never personally seen one, though I imagine a wooden bong would resemble a plastic bong without the assurance of being waterproof!
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