Coupons are a big craze right now with shows like Extreme Couponing and customers looking for any way to save a buck. If you have the ability to create a coupon offering savings on your products or services now is the time to do it.
Coupons are great because they give your customers incentive to buy at your store or business and it gives you instant feedback on your marketing. The trick is to make the promotion worth it to your customer and still profitable to you.
I would suggest watching shows like Extreme Couponing to see how consumers think and how couponing can work.