what every consultant needs to hear

This was received out of the blue yesterday after not having been in touch with a member of the Board of one of my existing clients for a couple of years (I guess all is going well!):

We have had such a good experience with ModPay at the {client name}, I would be grateful for information on setting up ModPay with a non-profit in Philadelphia... Would you be kind enough to call me at {phone number}?

Makes us proud to help and to be referred over and over again.