The Laptop Tablet by NAVIsis converts any laptop into a tablet.
It attaches to the side of your laptop monitor and plugs into a USB port.
It looks like you use the stylus directly on the screen, which can’t be good for all LCDs. There’s a reason actual tablets have a glass covering. Also, not sure if this works on regular LCD screens, I don’t see why it wouldn’t. But you should probably just use a Wacom tablet for your home computer anyway.