The AVH First Defense Against Spam plugin gives you the ability to block spammers before any content is served.
I'm in the process of setting up a new site for translating all my plugins. Please keep an eye on my website for news on when it goes live.
Unfortunately not. I don't believe there is one solution to block all spam. Personally I have great success with the plugin in combination with Akismet.
I'm currently not aware of any conflicts with other anti-spam solutions.
On the Internet when you click on a link, directing you to another page a HTTP referrer is set. If you type in an address or select a bookmark from your browser this referrer is not set. When somebody posts a comment on your blog, they click the submit button and are redirected to another page which handles the submission. At the moment the HTTP referrer is set. The plugin checks if there is a referrer, if there's not the connection is terminated. For a more detailed write you can read an article I wrote on my site
You can define two sorts of ranges: From IP to IP. i.e. 192.168.1.100-192.168.1.105 A network in CIDR format. i.e. 192.168.1.0/24
You need to have an API key from Stop Forum Spam. If you do on the Edit Comments pages there is an extra option called, Report & Delete, in the messages identified as spam.
You will have to sign up on their site, http://www.stopforumspam.com/signup.
You will have to sign up on their site, http://www.projecthoneypot.org/create_account.php .