Will probably build the system above for my old PIII 1u server. But if you are like me, you have several cots (computers off the shelf) systems. In that case, I just use generic shelving like below.
This other shelf will support the one 1u server, but the server is so noisy that I have not included it.
As you can see my equipment is sooooo old, might as well not do computing anymore.
Also used some coat hangers to make a keyboard shelf.