Would you use the phone if you had to listen to a 10-second brothel advertisement every time you made a call? That is the size of the challenge that confronts email: beat spam, or the medium will forever fall short of its potential.
You can block out 50 per cent or 75 per cent of spam quite easily. But as spam volumes rise, even a 90 per cent blocking rate can leave you glimpsing a daily dozen spiels for generic Viagra and "barnyard fun''. Yes, you can hit the "delete" key but this last 10 per cent wears you down. Anti-spam initiatives from AOL, Microsoft, Yahoo and the US Government seem likely to whittle the 10 per cent down only a little.
Can we block the last 10 per cent? Maybe. A technique called Bayesian filtering is capable of blocking more than 99 per cent of spam.
