Bedding:

Wood based bedding will last longer then paper based bedding. 

Paper based beddings are great if you have someone with an allergy. 

Wood based Beddings

If you wish to use wood shavings as litter, hardwoods such as aspen are one alternative to pine and cedar. Unlike softwoods, hardwoods do not contain any phenols. Similarly, softwoods that have had their phenols removed via a drying process, such as is the case with kiln-dried pine, are also safe for use.

Gentle Touch Litter consists of pellets made from aspen wood that are very absorbent and excellent at controlling odor.

Corn-cob bedding, available in most pet stores or feed and garden stores, is also non-toxic and safe for use.  However, it should be noted that this bedding is more prone to growing mold than other beddings, and is rather hard. There have also been instances of smaller animals, such as rats, choking on the corn cob pieces.

There are numerous safe beddings made from paper, recycled newspaper, grasses and other organic materials. The paper-based products are especially effective in that they inhibit the formation of ammonia, which helps keep odors under control. Some of these products are less commonly found in pet stores, though most of them can be ordered by your pet store, feed and garden or veterinarian.  Some companies will even ship directly to your home.

Of the paper-based beddings, Carefresh is arguably the most popular. It is created from wood pulp fibers that are too short to make paper, and is processed to the appearance and texture of shredded egg cartons. It is soft on the feet, making it a great choice for bedding.

Recycled newspaper beddings such as Yesterday's News, Crown Animal Bedding and Bio-Flush are pelleted beddings that are extremely absorbent and excellent at odor control.  Yesterday's News comes in both regular and soft-texture pellets. For animals that use litter pans, pelleted beddings are fine as-is, but animals that live in their litter may need a layer of softer bedding (such as timothy hay) on top of the pellet base to stay comfortable. Only a thin layer of pellets is needed as bedding; anything more than that is wasted.

Eco-Bedding consists of crinkled strips of craft paper (brown paper one grade below grocery bags).

Critter Country is a pelleted bedding made from wheat grass. The manufacturer claims that these pellets actually prevent the formation of ammonia.

Finally, timothy hay makes a safe bedding, although if you use it as a food source also, it's a good idea to put the portion of hay which is used for food somewhere that's difficult to climb into and that's differentiated from the rest of the bedding. Hay can usually be obtained from a feed and garden store, or directly from a farmer, but if you have trouble locating fresh timothy in your area, see the contact information for the Oxbow Hay Company, below.

 What's wrong with cedar and pine?

The liver being re-written

The respiratory system

The effects of cedar and pine on the respiratory system is clear, and well documented through several years of scientific research: the natural chemicals present in softwoods can damage the respiratory tract, leading to chronic respiratory disease and asthma. Although most of this research describes the effects of wood products in humans, it should be noted that the effects are likely to be more pronounced in small animals, who have a much greater sense of smell, and are therefore more sensitive to respiratory irritants.

The primary irritant in cedar is plicatic acid, present in highest concentrations in western red cedar. Although the mechanism is not fully understood, plicatic acid has been shown to cause asthma, and inflammatory and allergic reactions after long-term exposures. The natural irritant in pine, called abietic acid, also exhibits allergic responses, though these are much weaker than those induced by plicatic acid. However, the oxidation of abietic acid does form compounds that are rather potent allergens.

Pine vs. Cedar

For fairness, it should be pointed out that the evidence against pine is not generally considered to be as compelling as the evidence against cedar, and the claim that pine is unsafe as bedding is more disputed. As a general rule of thumb, pine is arguably less dangerous than cedar, but if you want to be safe, it's best to avoid both if at all possible.