Get a rugged case, either by buying one from here or someplace similar, finding one at a thrift store or hacking one from an old cordless drill case. Securely mount some heavy-duty velcro on the bottom of your laptop in locations that won't interfere with access to the battery or any other access you may need. Mount the matching velcro inside the case. Use the velcro to secure the laptop into the case. Fill in any gaps between the case and the laptop with foam, being sure to leave room to access your ports, drives, power cable, etc. If you really really want to, you can detach the screen from the base of the laptop and velcro it into the lid of the case (assuming the cable is long enough).