Interesting use of the date dimension table to calculate analytics. Expanding the model a little to add accounting weeks (in a 4,4,5 or similar rotation), quarters, years, etc. and following a similarly flagged (y,n or 0,1) field design provides a dynamic transition into data warehousing for the small to medium businesses that do not have the budget for a full blown data warehouse application. Then, you simply pair the flattened warehouse structures with SSRS and voila....basic management reporting 101. Nice post!