Take care of your car, and it could last 20 years, possibly 30 … or more. Though its styling might be out of date, it will still get you down the road.

If only we could get that much life out of our desktop computers and laptops. Granted, it’s a lot less expensive to replace your Mac than your Mercedes, but most of us still wish the rate of technological evolution would slow down just a bit … long enough for us to get another year or two out of our old machines before they’re too lame to keep up.

In 1998, the National Safety Council estimated that about 20 million computers per year were becoming obsolete. By 2007, the Environmental Protection Agency was projecting that number had more than doubled.

Once you’ve resigned yourself to the purchase of a new computer, what do you do with your old one?

• The garbage can: Not an option. For one thing, even though your processor may be slow, there are still plenty of perfectly usable components that can be reprocessed or reconditioned and used again. For another, some of the materials in “e-waste” can include lead, nickel, cadmium and mercury, which can pose environmental and health risks if mismanaged.
• Donating: There are programs nationwide that would be wildly happy to accept your clunky, slow computer for use with nonprofits, schools or low-income assistance. Your donations should be in working order and not too ancient. The bonus (besides helping your fellow man) is a tax incentive for your charitable contribution.
• Recycling: More than 1,000 U.S. cities offer some type of electronics recycling (e-cycling) as part of their waste management services. In 2007, 18 percent of computer hardware that had reached the end of its lifespan was being recycled, according to the EPA. You can find a recycling program in your area through EcoSquid, Earth 911 or TechSoup.