FYI: If you use Xchat with CBStream, Controlling Xchat in #cbstream already has this ability, more or less. You can ignore outright, ignore but be alerted that someone you ignored spoke (it'll tell you who), or basically get the full text with comments that it's from someone you're pretending to ignore.

It's all configurable, but once the message comes in and is ignored, you can't just mouse-over to see what they said - it's lost.

Note that the xchat plugin's ignore list is shared with perlmonks, so you can switch back and forth without losing who you're ignoring.

(This was done for one of the people who DO use the ignore a lot...)