Money on the internet is, for the most part, dependent upon current exchange rates and reserve bank stipulations from authorities outside the Internet. The current monetary model runs contrary to the very mutualistic sharing and copying of data and information on the Internet, and is best used for transactions involving tangible goods (CDs, DVDs, furniture, anything you can find on eBay).
Many companies have realized this, and have considered alternative Internet-based money-making schemes, particularly the concept of ad-based freeware.
Paying for data encapsulations, on the other hand, is regarded by those who are Internet-savvy as disingenuous and wasteful, as many data encapsulations, such as audio/video recordings, software executables, e-books in PDF, can usually be obtained for free on P2P networks such as Gnutella, Bittorrent, and eD2k.
However, one often-compelling argument for monetary currency on the Internet is that it is an incentive towards further, more refined creation of distributable material, such as software; another is that monetary currency usually helps in the payment of maintenance and bandwidth costs.
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