Value- What does it Mean?

The definition of value is an amount, as of goods, services, or money, considered to be a fair and suitable equivalent for something else; a fair price or return. When I look at that definition and consider how someone can pay 104.3 million dollars for "The Running Man I" it perplexes me where the value is in art work that is sold for that much. The piece was sold for over 5 times more than its estimated price, and people viewed this as a positive thing because the economy especially in the art world was not doing great and companies such as Lehman Brothers were selling whatever art they could for whatever amount of money to pay off their creditors. Did this anonymous buyer of the Alberto Giacometti piece think that this sculpture actually meant 104 million dollars to him or was this all an investment? The art world itself is confusing enough to me, but when money has now changed the definition of art- it becomes even more confusing.