Explains how captcha features can keep spammers from signing up for certain accounts online, such as email or weblogs. Explains how the system can be circumvented as well.
Report from the Center for Democracy and Technology analysing how email addresses posted on websites and in newsgroups attract spam, and how effective different obfuscation techniques are.
Neil Gunton describes his experiences with software programs browsing websites looking for email addresses, and the techniques he developed to stop them.