I'd have to disagree with Pook's assertion that for something to be commercially available it must be affordable to nearly everyone. I can't see how the word commercial implies any sort of egalitarianism. It simply refers to commerce, which typically involves the exchange of money for goods or services. The poor, by definition, will be limited in the amount of commerce they are able to participate in.
'Commerce' also implies everyday marketplace trade. I was emphasising the availability part more than the commercial part I guess.
