Binding of different sub-elements from the model

Hi,

I have a question relating filtering/binding of different sub-trees to ONE table.

I have a model, where I store "activities" under each "customer"'s node, e.g

[CUSTOMER_4711]

  [ACTIVITIES-A]

  [ACTIVITIES-B]

  [ACTIVITIES-C]

[CUSTOMER_0815]

  [ACTIVITIES-D]

  [ACTIVITIES-E]

  [ACTIVITIES-F]

So each customer node got [0...n] activities.

When I navigate trough the model I can use my customer binding context to display all activities link to this customer.

Fine so far!

My challenge is now, that I want to create an other screen with an table, where I can see ALL activities of ALL customer.

My current approch is, to traverse the complete model and create a temporary model.

I wonder, if there is an other solution to adchive this :-)

Cheers

Jens