Sometimes it's handy to have a talkback or headphone bus channel in the arrange. Unfortunately there isn't any suitable track header icon that enables you to spot it easily.
Hey presto... I made one
It's just a little pic of some headphones, which symbolises to me that it's something going to the headphone mix. Might be useful in a dj application as well. I dunno.
You have to drop it in Your name/library/application support/logic/images/icons
It's called 326 because 1-325 are reserved for logic's default icons. So don't change the name unless you've already made an icon called 326, in which case call it 327 etc.
Christmas came early eh