I didn't see this mentioned, if it was then oops lol
Have you heard of OH Cards?
http://en.wikipedia.org/wiki/OH_Cards
I always thought Tarot could be used as a variation of this sort of method. For instance I had a manager once who was a recovering drug addict. He always said the one thing that kept him going, and what helped him in the recovery process, was when he got into religion. Because he had turned to religion first before seeking the proper help he needed. I kinda wonder what help Tarot could actually provide psychologically, since there are all kinds of treatment methods and options spiritually and religiously. Tarot is both concrete and abstract, you have a very tangible tool that can be seen and touched. However the cards have all these concepts and symbols that almost compliment psychology and some of the abstract concepts surrounding thought and the psyche.
I have no idea if this story would help but it's a practical application I would think. One example I have from over a year ago, is I did a reading for a friend who had recently lost their grandfather. The question for the reading was framed, "Is there any sort of message my grandfather wanted to leave me." Regardless of the content of the reading, it was interesting seeing the change in how she handled her grandfather's death after the reading. Because she wasn't present at the hospital when he died and didn't get much closure, so she seemed most upset about that if anything. However during the reading she just opened up at different points and shared all these stories she had. So even if the reading was way off, it did seem to provide an opening point where she felt comfortable talking about what happened.
So it makes me wonder what sort of affect using Tarot could have on getting people to open up and handle some issues. I think there could be room for ethical problems as well, like imagine a psychologist using Tarot to have a patient relive a traumatic experience like rape or abuse. Reminds me of what happened on this show on the Style network called Ruby, where she went to a Reiki session and it seemed to unlocked some traumatic memories where she had to stop the session.