I used to work on and teach people to use automated test benches for the military. The bench I specialized in was built around a '70s-era Harris H100 mainframe: 512MB RAM, processor ran at somewhere around 3MHz and it had a whopping 20MB of hard disk storage.
I would hold up my PDA and tell my students that it could run the bench, if you could interface it right, and hold all our programs on the device.
Still waiting for the positronic brain...