Is the end nigh for email?Spam will eventually kill email says the inventor of the first commercial email application. Eric Allman, who wrote the world's first internet mail programme in 1981 and is CTO of Sendmail, said people will stop using email if the spam flood continues. He believes users are in the middle of a spam explosion and there is very little companies can do to prevent it from worsening. Allman said: "There is a genuine concern that too much spam will kill off email. We haven't quite got there yet, but it could happen." Allman said the main problem with spam is the fact that it's free to the sender and the only way to get rid of it would be to make the sender pay for the messages: "We must make it chargeable to the sender. One way would be to use e-cash. Every time a spam is received, the receiver charges the sender." However, this is only possible when the sender is known. Much of the email clogging up web mail accounts is not from the address it purports to be. UK universities have been particularly blighted by this problem (see http://www.silicon.com/a42837 ). Allman added that defining the ambiguous nature of spam is the first major hurdle to overcome. "There is no clear definition what spam is and what is not," he said. "If I sign up on someone's website and start receiving information from them, it's hard to say whether that's spam or not."