There are also dedicated backpack PCs that are designed to run in the backpack, usually for virtual reality. I think those are super expensive though... (search "VR backpack")
Also they probably take up the whole backpack instead of being "backpackable". And they might be built like laptops (proprietary form factor, mobile/ultrabook CPU, etc.) depending on the model.
Also they probably take up the whole backpack instead of being "backpackable". And they might be built like laptops (proprietary form factor, mobile/ultrabook CPU, etc.) depending on the model.