Connecting two cubes

I am using SSAS 2005 and I have a situation where I have two different cubes that I need to link up so that I can get related data from one cube to the other.

Here's the scenario:
I have a customer cube that gives me metrics about how many new customers, inactive customers, etc based on date ranges and other criteria. What I need to be able to do is once I have a subset of customers I want to be able to look at related measures that belong to a different cube. I have thought about making a large cube that contains multiple fact tables and allows me to grab both measures as necessary. The reason I'm trying to avoid this approach is because the customer data is going to be changing (a customer becomes inactive) and will require a full process on the customer cube. There are currently only about 100K customers, so the reprocess time is fairly minimal. The related data has several 100 million rows requiring a siginificant time to fully process. So, it isn't practical to have it all in the same cube where everything would have to be reprocessed. So, my questions are: Can I link two cubes together (sort of like virtual cubes in AS 2000) so that I can follow information across two cubes? Or if I did include a second fact table in the cube can I only process the fact table related to customer information and not the one containing the related data?

Thanks!

You should be able to create a 2nd measure group for the 2nd fact table in the original cube, but only process the 1st measure group:

http://msdn2.microsoft.com/en-us/library/ms175634.aspx

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Processing a Measure Group

When you process a measure group, Analysis Services processes some or all of the partitions within the measure group, and any unprocessed dimensions that participate in the measure group. Specifics of the processing job depend on the processing option that you select. You can process one or more measure groups in Analysis Services without affecting other measure groups in a cube.

Note:
You can process individual measure groups programmatically, or by using SQL Server Management Studio. You cannot process individual measure groups in Business Intelligence Development Studio unless you do so by partition. ... >>