Coffeematic PC – A coffee maker computer that pumps hot coffee to the CPU

Sometime during winter 2024, I found myself at a thrift store. I was staring at rows of appliances,
wrapped in plastic and clinging to life, trying to answer one question: which of these is the right
chassis for a retro gaming computer?

Driving home, I took corners carefully, checking that the General Electric (GE) drip coffee maker I’d
chosen was safe in the backseat. The coffee maker’s given name was Coffeematic. Circa 1980,
it is boxy yet athletic – unfazed by any considerations of future internet connectivity. Best, it is perfect for being hacked.

Coffeematic is now Coffeematic PC – part gaming computer, part coffee maker.
A newly synthesized machine percolating processes well beyond its original configuration.
Coffeematic PC is part of a lineage of coffee maker computers made since 2002.
I’ll describe that fascinating lineage here, and how it inspired an art exhibition called Sparklines
where hand-drafted data visualizations accompany Coffeematic PC.

Coffeematic PC, the final build of a coffee maker computer by artist Doug MacDowell

Profound and poetically articulated. Elegant and assertive. Highly scaleable with dynamic acceleration.
No. These do not describe Coffeematic PC or its peers (one of those phrases describes a bottle of wine.)
A custom built computer can be basic and functional, or an elaborate, absurd,
spinning piece of art. Coffeematic PC falls somewhere in that spectrum
while also being nearly self-destructive.

Coffeematic PC, a coffee maker computer in progress on artist Doug MacDowell’s workspace

This is how Coffeematic PC works.
The computer is fully functional. The coffee maker is too,
it percolates Java like a regular coffee maker. Very hot Java.
Computers usually use fans or liquid cooling systems to reduce heat.
Coffeematic PC uses the hot Java it brews to heat? cool? caffeinate? the computer.
A pump takes the hot, caffenated slurry (~90C/194F)
and circulates it thru two radiators sitting on top of Coffeematic PC’s crown ->
down to a central processing unit (CPU) tucked within an ASUS M2NPV-VM
motherboard snugly strapped to Coffeematic PC’s back.
Java continues through an artery returning to Coffeematic PC’s caraffe.
The process repeats until Java is integrated with the user or the machine is powered off.

Coffeematic PC coffee maker computer dispensing liquid, created by artist Doug MacDowell

↑ Coffeematic PC has a dedicated pump to aggressively dispense Java for user.

CPU’s are meant to be cool and Java hot. Despite circulating hot Java,
Coffeematic PC does not crash.
To understand more, I wrote command line code to gather data on Coffeematic PC every 5 seconds,
and monitored Coffeematic PC for 75 minutes.
The graph below shows the results.
The machine is just barely non-destructive. Coffeematic PC’s CPU, body,
and circulatory system eventually find equilibrium. A warm 33C/91F –
amazingly close to the temperature of the slurry that flows through you and me.

An important part of this project is the lineage of coffee maker computers.
Before discussing that,
this is how Coffeematic PC was made.
The build is a mix of discarded electronics and newly purchased
hardware, pumps, and radiators. The motherboard, CPU, RAM, and graphics card are from the mid 2000’s and were
sourced from a recycling center. This is a parts list for Coffeematic PC.