g1smd - 1:22 pm on Apr 23, 2012 (gmt 0)

Wait. Hold it right there and then back up one.

URLs for product pages do not need to specify any of the category names as folders.

Sure, list your products in categories and have a heirarchy of categories, but don't specify category names in the actual product URLs.

The benefits of this will be blindingly obvious once you try to implement any sort of multi-faceted navigation system.