Uni-taskers
Devices such as My Typewriter (Hermes 2000), not multi-taskers, but devices that doe one thing best, and one thing only.
Another device, My Distraction-Free Typewriter (Micro Journal).
Origin: My Typewriter (Hermes 2000)/ Stolen Focus- Why You Can’t Pay Attention (Johann Hari)
References: Productivity, Finding Flow