Broad range of incentives includes cash back from employers, discount insurance and free parkingMany government agencies and companies have recognized and encouraged the use of hybrid cars and trucks with a variety of perks — from tax incentives to HOV (high-occupancy vehicle) lane access to free parking — even $5,000 cash back from some companies. With a little research, thrifty hybrid buyers can save time and money while they're saving the environment.

Perks for hybrids can be grouped into four main categories: government tax credits and rebates, exemptions from regulations like parking fees or carpool lane access, employee cash back and consumer discounts. New hybrid incentives are emerging all the time and existing ones change frequently. In some cases, different rules apply depending on the location or the model of the hybrid. Keeping up with the current status of any one incentive can be challenging, but several Web sites offer reliable and up-to-date information, and we'll list them here.

All levels of government cater to hybrids Federal, state and local governments offer a wide array of tempting incentives for hybrid buyers. At the top of the list, the federal tax credit for hybrid vehicles uses a sliding scale based on the car's EPA fuel economy data and also involves quotas for each model. Both the IRS and the EPA have explanations and updates about the tax credit on their Web sites.

Many states also offer incentives for hybrid buyers, primarily tax credits and access for solo drivers using the HOV or carpool lanes on interstate highways. Some of these perks apply only to hybrids with the very highest fuel economy. HybridCenter.org maintains a detailed and frequently updated list of states' hybrid perks.

Unfortunately, no two state policies are alike, and to make things more confusing, these laws are being refined, expanded or expired all the time. The Department of Energy has designed an easy-to-use Alternative Fuels Data Center , listing government incentives and laws with Web links and phone numbers. The Web page advises researchers to contact the state sources to confirm the current status of any regulation.

A growing number of cities offer free or reduced parking rates and other special privileges for hybrid vehicles to encourage environmentally responsible car purchases. Most of these programs are limited to local residents, and many are short-term pilot projects. Your municipal Web site may have information, but usually the quickest way to determine whether a city offers any hybrid incentives is to call the local city clerk's office.