Pro: These large filters (usually 20" by 20") are sold at every home improvement store. They are very inexpensive, about $0.50 each.

Con: This material is designed for high volume air systems such as HVAC. For smaller air volume applications such as computers, they are not very effective at trapping dust. They are also hard to work with because of the thickness of the material (usually 3/4").

Pro: Yes panty hose is a common method for dust prevention. They catch most particles well and readily available at any grocery store.

Con: They are very hard to work with and even more difficult to adhere to computer cases, glue has to be used to make the bond. They also snag very easily.

Pro: uhh... I don't think so...

Con: Very expensive and only available in large rolls. Also restricts airflow immensely. Not recommended.

Pro: This material is easy to work with, and catches most size dust particles.

Con: Expensive and only available in large rolls, after all its designed to be a weed barrier. Also varies by manufacturer, some restrict air flow too much.

Pro: This is the best material to use. It's inexpensive, doesn't restrict airflow, and catches most dust particles. It is also washable.

Con: Not readily available in hardware stores.

Pro: Doesn't restrict airflow at all, and is available at any hardware store.

Con: Only catches very large particles.