So you would like to get some work done while walking on a treadmill? The VIVO Universal Treadmill Desk Riser has you covered. It is a height adjustable platform for laptops and tablets. This 29.5 x 11″ desktop riser is secured over your handlebars with velcro straps.
This treadmill desk can be adjusted from 1.8″ to 13.9″. It can handle laptops up to 11lbs. More information is available here.