I can't believe it took me two years to figure this one out. Unfortunately, it won't work for everyone. But if you have a 'spending account' card, it will work for you.
In case you don't know, a spending account card comes from your insurance company. At the beginning of the year, you put a certain amount in the card. It's your money. This is like a debit card, except that it has a specific purpose. In my case, to buy medical things or services. Everything medical that is not covered by my insurance can be paid for with this card. (You have to use it up within the year or you lose it. And it comes right off the top as a tax deduction.)
That includes most OTC meds, which is where the CVS trick comes in. The other day, I used the card to stock up on some cold medicine, bandages, etc. One product gave me $3.00 in ECBs. I was also picking up some fabric softener that was BOGO (yes, I use vinegar and baking soda, but sometimes I just want something that smells nice), which made it 2 for 3.99. So I used the $3.00 ECB and got the softener for about 50 cents a bottle!
I hope this helps a few people out there to save a little money!