I recently read a book by T. Scott Gross, Positively Outrageous Service. His ideas of providing outrageous customer service are just what we need.
Are you satisfied with getting a new customer, having them buy from you once, and then never seeing them again? Of course not! We want them to come back again and again and to tell all their friends about our business. How do we get them to do that? Provide outrageous customer service.
Every once in a while do something totally unexpected and over the top for one of your customers. See if it doesn't get them coming back and telling everyone they know about you and your services.
I highly recommend that you read Positively Outrageous Service and think about what you can do to provide it to your customers.
I'd like to hear what you've done for your customers that keeps them coming back.