Most people have thought of the lava lamp case mod. I'm imagining a step further.
What if the lava lamp was the size of two disk front panels, rectangular and similar construction as double glazing. Quite thin. If you had a large system, with a lot of computational power, the size probably could be
extended to the side of the tower.
The inward facing side of the glass sandwich is like a Lego base plate with the lugs pointing internally. The sandwich is filled with standard lava lamp solutes and solutions. The lugs, arranged in a grid pattern, have an indentation externally that can be plugged into. It might be smart to have the sides and bottom edge have lugs as well.
Insulated pipes, think Technic pneumatic pipes, carry a heat conducting fluid and can be plugged into the glass lugs. The other end of the pipes have clips which can be attached to various components inside the machine. These can be placed on different areas of the heat sinks or on heat coming from the power supply. If the computer has water cooling, a cold line can be drawn from the freshly cooled coolant.
In summary, this lava cmd allows the installer to choose hot and cold points on the glass lava display, to control the lava in a uniquely personal way, for a uniquely personal computer.
The computer's own LEDs would probably back light the display window and add to the visual artistry.