I am needing a desk maybe about the size of one of those couch trays or whatever you want to call them that fold out to a tray so you can sit on the couch and have something to put your food on. I might want it to be a little bigger tho as i need to put my mouse and keyboard on it. I want something that is very adjustable. That can go up to a decent height and can also go lower and still be usable. Sort of how most desktop chairs are made. Is there a desk out there with this capability?