i recently had a back injury and had to make a change to my workstation. i got the Ergotron Workfit-s sit/stand workstation - http://www.ergotron.com/Products/tabid/65/PRDID/380/language/en-US/Default.aspx
it is a desk attachment that mounts your keyboard/monitor/mouse + laptop to a stand that easily raises and lowers to between sitting and standing positions. it literally takes 2 seconds to switch from one position to another. i now switch between sitting and standing several times a day. it is so easy with the Ergotron that I hardly think about it, there is no hesitation.
a really nice bonus is it positions the laptop in a way that it can be used as a second monitor.
http://www.youtube.com/watch?v=EV_i_mi---w&feature=player_embedded