Ever since people started integrating software into the LEGO ecosystem, the machines have gotten vastly more complex and ambitious. Now, the platform has had some time to grow up and folks out there are designing LEGO machines that can make other things! Most of the things you would expect to find in a machine shop are represented in some form. I found videos of a bunch of them, starting with some designs by Arthur Sacek. Check out his CNC foam lathe:
In addition to the lathe, he has built a desktop milling machine, and a very impressive rotary mill. I also found a 3D printer that prints in LEGO bricks, a 2D dot printer and a loom. There were digital capture tools as well, including a 3D scanner and 2D scanner.