There's always this option:
http://www.lifespanf...0-dt3_model.jpg
I think it would be less likely to become a clothes hanger than you might think. I currently use a tablet when I am on my elliptical cross trainer, and I love it. I also did something like this about 20 years ago with a computer monitor and keyboard mounted to my treadmill. This was before most people had internet access, but if I wanted to use my computer, I at least had to stand on the treadmill.