I'm an avid reader of Speaker's Corner, and often find that I wish some people would just not appear in threads. So I sat down and wrote this script for Firefox, which works with the Greasemonkey addon.
Basically, it lets you do two things:
1. Create a list of favourite forum contributors. The script will highlight any messages on the page from these people (by adding a thick black border)
2. Create a list of less-than-favourite contributors. The script replaces any messages from those contributors with a button. Clicking the button reveals the message.
Here's the script: http://somethingchanged.com/file_download/4/sgforumsblockcomments.js
Set the user names in the top of the file, and add it to your Greasemonkey add-on.
Here's a screenshot of a highlighted user immediately followed by a hidden comment:
(I chose the thread and users completely at random so as not to offend anybody at Speaker's Corner)
And another showing the comment revealed after clicking 'show comment':
Let me know if you need any advice on how to set this up with Greasemonkey, or any feedback you have.