I work standing up most of the time. I prop my laptop up on an Ergotron extension arm http://www.ergotron.com/Products/tabid/65/PRDID/317/language/en-CA/Default.aspx[^] fitted with the laptop tray. The one trick is to have the bluetooth keyboard sitting at waist height so you don't end up scrunching your shoulders and getting a sore neck/shoulder. Been working like this for over a year and won't go back to sitting only.