It is said that about 90 percent of all e-mail messages are spam. By charging a small token amount for each e-mail sent, it would make mass mailing of unsolicited advertising extremely uneconomical. Considering that the worst spammers send out up to a million emails – per day – this would make spam a very unprofitable business.
The idea is thus to reinvent the old stamps, albeit in digital form. Yahoo is currently working on a service called CentMail where each stamp costs one American cent (7 öre). For five dollars you buy a digital stamp booklet consisting of 500 stamps. But instead of Yahoo adding rhubarb to the money, the money is instead forwarded to a charity of the user’s choosing.
CentMail is still under development, but if you want to be informed when the service is launched, you can go to the website and sign up.
Source: New Scientist.