zen doodle letters- negative space *NOTE* this is a GREAT site for zentangles, how-to's, and great examples. For diy, look up zentangle patterns and trace around whatever letter. Great for framing and embroidery!
I never thought about it being a "zen" thing but I've done this sort of doodling since I was in middle school and come to think of it, I'd do it when I was nervous, upset, or overwhelmed. ( I usually 'doodle' when I'm bored)