of a free rental van for four weeks. Why four weeks? To get people into a habit of using his service. The result? 19.6% redemption rate and as many as 65% of the people who took up the free offer went on to become regular customers.   Case Study # 2 - Health Club   A health club gave away six weeks of free memberships has saved a fortune on conventional advertising costs by having health food stores and sports shoe retailers give their free membership away to their customers as a special gift. The majority of free trials tuned into paying members at over $500 per membership.   Case Study # 3 - Optometrist   An optometrist mailed a postcard to prospects offering free eye exams, including four different types of eye tests (dry eye test, glaucoma test, visual acuity test, cataract test) to patients they hadnt seen in two years. The optometrist grossed an extra $10,000 in two days and the phone rang off the hook, non-stop.   Case Study # 4 - Oil and Lube   An oil and lube center offered a free tire rotation, oil change, and fuel injection service. However, the customer was only allowed to take advantage of one of these services per visit. The free service giveaways resulted in significant up-sells on each visit and the opportunity to capture the customers personal and automobile information for future offers.   Case Study # 5 - Hair Styling Salon   A hair styling salon offered a free childrens haircut with every visit. Most of the customers brought an average of two to three of their children to get their hair cut, resulting in a doubling of their weekly sales figure.   Case Study # 6 - Chiropractor   A chiropractor offered a free back massage gift certificate for Valentines Day with a free new patient exam including an x-ray, neurological and orthopedic exam. To make this offer super-successful, he went around to local businesses and gave several gift certificates to the local owners and managers to give to their employees as a free gift.   Case Study # 7 - Dentist   A local dentist offered a free teeth-whitening with a comprehensive new patient exam, including x-rays. To make this particular offer a winner the dentist sent several coupons to existing customers who had already received the teeth-whitening service, to give to their friends as a special gift. To make it even more effective, he coded each coupon and offered three free whitening sessions to the customer that sent in the most referrals.