As a GTDer I find myself processing a lot of paper (rather than just letting it stack up). This has meant more desk time for the implementation period. Due to a back injury I have found it useful to do some work standing up. For example, I am filing into cardboard bankers boxes for now and I have lined them up on a table. So much easier than bending. It is making me thinkabout a stand-up desk. Anyone considered this? Is it realistic? I also use an exer-ball as a chiar while keyboarding and I highly recommend it. Do easily get bored sitting? Do you want to stronger core back and ab' muscles? If the answer is yes, you might consider using a large inflatable ball as a chair. The ball should be big enough and inflated enough so that your knees bend at 90 degrees. I am not sure if there is a rule of thumb for determining the correct height of the work surface for keyboarding, drawing, or handwriting, but might want to consider that. I understand there are chair frames that can hold the ball up but have not tried this.