This question is to see if anything would need to be changed in my SQL query, other than the setup of the report.(I know how you guys are with the site rules ;) )
I want to run an automated report that generates a seperate list of open cases for each customer.
Here's the tricky bit: How could I get SSRS to run this as a separate report for each customer?
If you are using Enterprise Edition of SSRS, you'll have access to Data Driven subscriptions, which allow you to use queries to pull report parameters and subscription settings out of a database. With a data-driven subscription, you could have a report run for individually multiple clients, and then delivered via email, file share, or other more custom options if you're willing to write your own delivery extensions.
Your query for the report will simply need to be parameterized in such a way that the report is already capable of being run for one client at a time (for example, a "ClientID" parameter).
See here for getting started with data-driven subscriptions (Lesson 3 Step 5 specifically for setting a parameter value):
http://msdn.microsoft.com/en-us/library/ms169673.aspx