I've been working on this site - I used the phpdug script to help me get a quick start. I assumed that if I forced users to login in order to post links in this digg-like website, there would be no need for a captcha. This has not worked as you can see all of the car spam. Is a captcha necessary even if I force users to login? Also, is ther ea captcha you can recommend that is easy to read (I have trouble with a few capchas sometimes, get frustrated, and leave websites). http://fantasybookmark.com
Well I would only use a capacha and e-mail verification for the signup process. You shouldnt need to make a capacha when posting. You could count how many posts have been made by that user in the last ten minuits, if it exceeds a certain value then make them awnser a capacha.