The word you're looking for is "asset", and mediums of exchange are by definition always assets. When people talk about their aspirations for Bitcoin, the most techno-utopians want it to become a commonly accepted store of value or unit of account.

Keep in mind that mediums of exchange can be seen as purely "any mechanism that can signal the irrevocable transfer of the value". The innovation btc brings to this is instead of transferring physical items you create cryptographic hashes that you then publicize.

It's worth noting that when we talk about money we're trying to describe emergent phenomena. This is what we've got, and the following items are just useful ways of thinking about the issue - except unlike in physics we don't have the leeway to conduct careful, repeatable experiments.

http://en.wikipedia.org/wiki/Asset http://en.wikipedia.org/wiki/Medium_of_exchange http://en.wikipedia.org/wiki/Store_of_value http://en.wikipedia.org/wiki/Unit_of_account

I forget the (accounting/financial) term for talking expenditures like videogames or movies or haircuts. I'm pretty sure we can describe those all as "services" but I've yet to find the appropriate wikipedia article. If someone can jog my memory that'd be great.