A fairly basic build overall, we have some CCK types for the products and views to list the groups of mats (i.e. Industrial Mats - http://www.deruijterusa.com/industrial-mats). We made a taxonomy of mats that the views use, you just tag the mat as one or more categories and they get listed. Kind of proud of the Part Numbers and the neat jQuery we have going on there.
Some non-standard modules we used include Node Images, Pathologic, and Header Image.