I know it seems a weird thing to do, but every now and then, I try drawing with my non-dominant hand (in my case, my left). The idea was used as one of the exercises on the Surface Pattern Design course I completed earlier this year. You get a different kind of line, and a different kind of style to your usual way of drawing.
I was surprised by the degree of control I actually had. And I liked the scribbly lines. More importantly, I think using the non-dominant hand reduces the weight of expectation, slows you down, and forces you to focus on the shapes rather than what the drawing “ought to” look like. I think it helps to switch out of language mode (as in, I’m drawing an ink bottle, I’m drawing a glass jar) and into a purely visual mode where you just concentrate on where the next mark needs to be in relation to the others you make on the page. (Betty Edwards is a keen advocate of this approach to drawing in her book, Drawing on the right side of the brain.) I even wrote a page of text, and it was fairly legible, although the loop of the letter ‘g’ caused a bit of confusion as to which way it should face.
If you give it a go, let me know what you think.