Comment verification code?

Oct 25, 2007 at 2:54 AM
Hi all, am a bit of a newb and have managed to get my instance of BlogEngine.NET up and working - I even managed to get it working with SQLExpress 2005 yay!
My question relates to restricting spam in the comments area. I don't want to have to restrict comments to be only available to registered users, yet I don't want spammers dropping in links. Has anyone employed those code verification methods into their site? They are the ones whereby you have to type in a code that is referenced by some sort of supplied picture.
I hope I have explained myself clearly enough!