Package builders give a unique way to sell products through a website. Jewelry websites use them to put gems with settings for a complete item. Bike shops for frames, wheels, seats, etc. The “builder” should have sliders for ranges of prices, quality scales, etc. Ajax would be nice too so users can see a list of inventory change on the fly and add components to their shopping cart.
If anything is out there, let me know, otherwise I’d love to see it here.