effective coupons

What was the most effective coupon you've ever offered for your online business? Any ideas as to what made it so successful?

The best coupons are:

1.) advertised on every social media site/outlet you have access to,

2.) visually arresting, with easy-to-read text, and

3.) create a sense of urgency

Coupon distribution is as important as the way a coupon looks. Consider mass-emailing your coupons, use social media to let everyone know about them, and consider using Craisglist to distribute them as well.