I am lately very much thinking about intrinsic and personal value of products. I wrote a piece named '6 factors of product value' at http://www.codawatch...-product-value/
I am talking here about factors that are something else than the standard three - functionality, cost and design. Factors I mention are the use of a product in a ritual, the capability of a product to retain a memory, symbolism, personalisation, durability and the value of gifts.
Do you know additional factors for value? I would love to hear it.