There is a reason the earth-friendly mantra is "reduce, reuse, recycle". Having fewer things means less to throw away. Finding a new use for an old item allows you to save money and repurpose something that was just taking up space. Recycle is for those items that you do have and are finding difficult to repurpose. The last thing you want to do is consign the item to the landfill.
One of my coworkers proudly stated that the plasticware and cardboard containers provided by our company's food service is biodegradable. The cardboard is made from recycled paperboard, a positive move, but is coated in plastic so moist food can be added to the container for eating and storing. The cups, utensils and soup bowls are made from plant-based plastic PLA. On one hand, the corn starch-based items are made from a renewable resource. On the other hand, a home compost system is not going to break down PLA.
When I pointed out that unfortunate fact (the compostable plasticware will not break down in a backyard composter, only a commercial one), she informed me that it will biodegrade in a landfill. Unfortunately, that is not true. Most composting happens under aerobic conditions with water, heat and microbes with a nice stir to add oxygen occasionally. A landfill is lined with clay and plastic, items are packed in tightly and the few microbes found are working anaerobically, that is without oxygen. So no sunlight (for photodegradable items like plastic bags), no water and no oxygen means little breakdown is occurring in a landfill.
The truth is once an item is sent to the big hole in the ground, it just sits there. That is why "reduce, reuse and recycle" sends fewer things to the landfill, keeps more money in your pocket and stimulates the imagination (e.g., what can I do with a penny whistle, some old nails and a plastic cup starting to split). For more information on biological activity in landfills, visit the following links:
How Stuff Works (love this site)
Summary of Garbage Breakdown (about.com)
US Composting Council (technical but interesting page)