While on the My Account screen, you can scroll down to the bottom to see a section called Ignored Users.
Clicking the "View your ignored users" link in that section will take you to a page that has an empty text box, in which you type the username of the person you wish to ignore.
Once the correct name is entered, click the Ignore User button and their name will appear in the list beneath the button. If you later change your mind about ignoring someone, you can click the Delete link to the right of the person’s name. Their name should disappear and you will be able to see their posts again.
Additionally, on any page where a post by the user you wish to ignore appears, there is an Ignore User button. This will also add the user to your ignore list.
Additionally, on any page where a post by the user you wish to ignore appears, there is an Ignore User button. This will also add the user to your ignore list.

I find it so much more fun to
Still, it's a question that
Oh, I know. I mean, this
If there is a particular user who is so disruptive people feel they should be programmatically ignored, odds are I'd just as soon ban such a person.