The machine John Titor came back for.
A working IBM 5100 — the first computer the world could actually carry. Sold as a complete archive: the machine, its printer, its manuals, and a lot of data cartridges.
Powered on. Fully operational.
Watch it power on.
No emulator, no photo trickery — the actual machine, switched on and running APL on its own 5-inch CRT, fifty years later.
Fifty-five pounds of the future, in 1975.
Six years before the IBM PC, IBM built a computer you could pick up and carry out the door. The IBM 5100 packed a processor, memory, a keyboard, a tape drive and a built-in CRT into a single case — something that had filled entire rooms only a decade earlier.
Inside runs the PALM processor, driving APL — the dense, symbolic language of scientists and engineers — on a crisp 5-inch screen. At launch it cost between $8,975 and $19,975: this was a machine for laboratories, universities and NASA, not living rooms.
This one is a Model A4: the top memory tier, 64K, configured for APL. It powers on, and the screen still glows.
Control panel — the "64" sets full memory.
A time traveler said he needed exactly this computer.
In late 2000, a poster calling himself John Titor appeared on internet forums claiming to be a soldier sent back from the year 2036. His mission, he said, was to retrieve an IBM 5100 — because it held an undocumented ability to translate between legacy IBM mainframe languages, exactly what his future needed to debug decades-old code.
The time travel is legend. But the strange part is real: the 5100 could emulate IBM's big mainframes through hidden microcode — a capability IBM never advertised, and which engineers who worked on the machine later confirmed.
Two decades later the story still runs — echoed by the cult anime Steins;Gate and its "IBN 5100." It's why, for collectors, this isn't just hardware. It's an artifact.
// The time-travel claim is folklore. The 5100's hidden emulation capability is documented.
The screen, alive — photographed powered on.
Everything in the crate.
This is a full-system time capsule: the computer, its printer, its media, and the paper that came with it — assembled and preserved together.
IBM 5100 · Model A4
The computer itself — 64K, APL, 5" CRT and full APL keyboard. Powers on.
IBM 5103 Printer
The matching period printer for the 5100 system.
DC300 Data Cartridges
A generous lot of original IBM quarter-inch data cartridges.
Original Manuals
An extensive library: APL references, service manuals, reference cards and IBM catalogs.
Professional Crate
Custom wooden crate with anti-static packing — ready to travel safely.
Up close.
The exact configuration.
Verified against IBM's model conventions and the unit's own control panel.