ToME: the Tales of Maj'Eyal

So does anyone have a practical use for those?

The problem I have is that these items require that you wait until you finally find the proper tier 5 white items to get the most use out of them.. but by the time you find tier 5 items, you usually find other items / artifacts that are stronger than a crystal weapon or armor.

Is there any class that can get a really good use out of them? There are some interesting options, like applying the focus to a glove or staff..

You can give the Crystal Focus to the Apprentice Mage for the quest I guess. That's the most use I ever got out of it.