Customer surveys are a very popular way of guaging the performance of an organization.  Here are a couple SharePoint options available to you.

 

1) InfoPath form-based survey.  One of the Microsoft Fantastic 40 SharePoint templates is called Business Performance Reporting.  This template is basically an InfoPath survey form and a data view web part which provides a slick XSLT chart of the reponses in the forms.  The advantage of this style of survey is that you can email a form to a customer, have them fill it out, and then upload it into the form library.  Of course, this is also the disadvantage - not everyone has InfoPath. 

 

2) Survey list-based survey.  The out of the box SharePoint survey list can be used to achieve the same thing as the form-based survey.  It has the added benefit of being able to be completed by a customer over the web, and can also easily include branching logic (e.g. the next question depends on how you answer the current question).  Basically it provides the same capabilities as your typical web-based survey tool.  If you want to use it for anonymous surveys, you can simply configure the survey list permissions accordingly. 

 

I've created a demo site that includes both approaches using pieces from the Business Performance Reporting template.  I put the chart of responses for the form library into a view also and made this the default.  You can compare this with the graphical summary view for the survey list - they are very similar.  You can download the template from Codeplex.