That is the cost of the device- apparently the price dropped. You can still
find it for over $250 USD...
That said I'm not sure how many BTC it produces. You may need a boatload of
these to make any real money from them.
However it could be useful if you want to create an anonymous source of money
to use for payments. If you pay with a credit card for bitcoins for instance
and then send the bitcoins received to another user for something somebody
else could trace it back to where you bought the coins from and since that
company has a record of your credit card they could identify you.
On the other hand if you have purchased this device and generated your own
coins from it your the original source and nobody can identify who you are
unless you make an association when you go to make payment for something.
For instance you could buy something virtually (entertainment content) or
contribute to a cause without being identifiable.
Examples where somebody might do something like this is: Middle eastern
persons whom are looking at entertainment content online that there
government doesn't like. Or for that matter Germany or the US.
Other examples might be a person in the United States wants to contribute to
a campaign to legalize something wrongly perceived to be horrendous. However
a public donation would result in criminal, social persecution, loss of life,
or job, even though not technically illegal (because it's political speech,
and the advocacy is to legalize).
An example might be a user of marijuana wanting to contribute to a campaign
to legalize it. While the campaign is not illegal the government might trace
the donations and persecute those donating based on the assumption (legal or
otherwise) all those who want it legalize probably are users (and thus
criminals). This isn't a great example although I'd be afraid to put forth a
good example.
