Tomorrow the Australian "Spam Act" comes into effect. After that, Electronic Messages...
a. must not be sent without the prior consent of the recipient. That consent may be express or implied ("reasonably inferred") from the conduct, business and other relationships of the person or organisation concerned;
b. must contain a functional unsubscribe facility; and
c. must accurately identify the sender of the message
Penalties run to over a million dollars.
Unfortunately more than 90% of our spam comes from overseas, mainly the U.S.
Hopefully all other countries will soon follow suit.