This is the simplest yet most effective design I've created yet. I took inspiration from daGHIZmo's supports, while adding a hole to lock the two pieces together for ease of storage and transportation.
The model included works great for my pc (Clevo P650SG), but I also uploaded the .scad script with several parameters for you to customize it.
You also choose the symbol you prefer engraved on the side.
Be careful not to close your lid while using this! You might damage your laptop if you forget the support is in the way and push too hard over the edge of the screen.
I got used to suspending it by pressing the power button, but if you want to keep using the lid this design is not for you.
It's a very simple print, so there are no mandatory settings.
It can be printed vertically for the best performance, but the columns end up being very weak and prone to breaking at the base. I recommend printing in on the side (as in the uploaded models) with few supports for the small cylinder (easily removable in that position) for durability.
The fitting hole for the smaller cylinder is a perfect fit on Openscad; you might need to polish some plastic off the smaller column or from the inside of the hole.
Don't force it in too much on the first try or it might get stuck.