Step 1: Sell said customer a new digital camera for $200. Not the one he really wanted mind you, but his second choice but still a very nice camera he's sure to like and use for some time. Oh, and make sure you have a 15% restocking fee for returned cameras if they are opened.
Step 2: When that customer comes back into the store later that evening with an ad for a competing store showing the camera he just bought earlier that day is $40 less, tell him that the competitor has to have one in stock for the price match to be valid. Oh, and make him wait about 15-20minutes during this process.
Step 3: After calling said competitor, or at least making appearances that you have, and type some random things in a computer screen that is too far away to be seen, come back and tell him that no stores have any in stock and that he's plum out of luck.
Step 4: When that same customer calls back a little under an hour later telling them he's headed BACK to the store a SECOND time because he has confirmed that a store in the area DOES in fact have the camera in question, be sure to put him on hold at least 3 times. And each time, keep him on hold long enough for the phone to start ringing through again. They love that.
Step 5: Ensure that your customer service reps make statements like "Oh, you're still trying to figure out the camera thing", and "this is ridiculus" or best yet, "Just do the $159.90 and be done with it." while within ear shot of the customer.
Step 6: Mention something to the effect of how the price would be $179.00 instead of 159.00 while within ear shot of the customer. Make him come over and explain the concept of "In Store Price" to you.
Step 7: Ensure he waits long enough to really draw a comparison to the service he is getting here compared to the competitor's store he just left. You know, the store where 3 employees all helped him track down a phone by checking 3 different inventory screens, calling two different stores, even though he told them up front that he'd already bought the camera else where and was just trying to get a price match. Yup, all that help knowing that they wouldn't get a dime more than the $18 he'd already spent on some card stock during his first visit. Really drive home the comparison for the customer as he sits and steams while you try to figure out how to drive him off even faster.
Step 8: At last, nearly grudgingly, do the price match. Barely say anything while doing it, just staple the price match adjustment receipt to the original, push it across the counter, and state your canned 'Have a good evening.' while he leaves.