This is my favorite right now, it's the ultimate utility knife. I use it for shaping hearts pushing glass, making the butt on a heart.
It's toward the bottom of the page.
http://www.howacoglass.com/tools.html
Regarding the didys, I thought for 104 glass that the didys were more for comfort and so you could see the glass better than for protection (I think I read that somewhere but I am not sure where). It seems I was misinformed. I have never taken a class though.