David Fiske Affiliate Marketing & Web Development

If you run a blog and you enable comments, please don't lock the comment form behind a user login. I've come across a few recently where comments are enabled but I'd have to sign up to comment.

That's a sure fire way to make me not comment, and probably not return as sometimes the comments are as interesting / more intersting than the blog post itself.
 
I understand there's a stupid amount of spamming on the web but there are plugins to counteract all that. A login makes it easier for you to ban a user, but also makes it difficult for "day trippers" to leave their opinions.