Picking up the computer theme... this is the 305 RAMAC (Random Access Memory Accounting System), the world's first hard drive that was introduced by IBM in September 1956. At the time, the hard drive/processor/power supply unit etc. took over a whole room of about 9m (30') by 15m (50'). And there I was thinking my father-in-law had been telling porkies when he said he'd entered a computer!
It may look nothing like a Mac Mini, but this computer was a revolution since it could store up to 4.4MB of data (5 million characters) - an enormous amount of data back then. The data was stored on fifty 24 inch magnetical disks. The entire RAMAC unit weighed over a ton and had to be move around with forklifts and delivered via large cargo airplanes. More than 1000 systems were built and the production ended in 1961. IBM leased the computers for $3,200 per month.