This is my design of the idea seen in some of the latest LinusTechTips videos. I am sure they will eventually come out with a great product so do check out their store, but for now, we can make our own!

There are two versions normal and channel. Normal has thick side walls and chamfers on the inside and so is good for cable end points. The Channel version is good for running a large number of cables up a leg of a table.

Assembly (if you can call it that 😄)

My design is made for magnets 10mm in diameter and 3mm thick. I will leave the link for the ones I have however you can modify the model to use ones of your choice I have uploaded all of the CAD files.

https://www.amazon.co.uk/Magnet-Expert%C2%AE-10mm-thick-Neodymium/dp/B00TACG90Y

The model also has some channels for adding rubber feet. This makes them hold really well and prevents them from sliding around. Most 3M style rubber feet have surrounding rubber which you can cut out and use for this. This is not mandatory but could be useful for some main channels which have many cables in them.

Modify

This is an open-to-use model feel free to change it and make your own versions, cable management is a personal thing.

Magnet and cable hole dimensions are defined in Fusion 360's parameters so you can make it the right size for you.

Height and Width control the size of the hole for the cables.

The magnets are designed to be pressure fit there is a test model if you wish to experiment with a few diameters (make sure you print the holes in the same orientation). You can also always glue in the magnets if you wish but it is not necessary.

Magnets!

Have even more cables? You can connect two holders together. The magnets provide a great mechanical connection you can even twist the parts to insert more cables.