You can export your customers to excel which can be convenient to analyze customer data in different ways as well as to create mail merge mailing lists for customized needs such as use with Constant Contact or other e-mail blast systems. 

To Export your data, simply click on Export Customer to Excel option from the Customer Accounts Menu as shown below

You will see a status dialog letting you know the export is occurring while the export data is being prepared.  The length of time this window will remain on your screen depends upon many factors such as how many customers are being exported, speed of your network and speed of the computer doing the export.  Once the export is completed, the exported file will be opened in your favorite spreadsheet program. The following screenshot shows the exported customer data being opened in Microsoft Excel: