Never answer questions on an empty stomach!
Obviously, as you point out, you can see this in the Resource Usage View
if you insert the Project field. Here is some simple VBA code that gives
you a hook to the list.
Sub ExportPoolLinks()
Dim A As Assignment
Dim R As Resource
For Each R In ActiveProject.Resources
For Each A In R.Assignments
Debug.Print A.Project
Next A
Next R
End Sub