Be smart, stay dumb.

Back to the sheet Office Calculator · C4
Photo
C4 · Level 0 · No electricity Dumb as a rock

Curta calculator

Curta Type I mechanical calculator, 1948–1972.

$1,000–2,000Buy on eBay
Estimate. Prices change.

Curt Herzstark designed it in a concentration camp and built it in Liechtenstein after the war. Turn the crank and it adds, subtracts, multiplies and divides. Collectors treat it like a watch.

Repairable
Opens with common tools, spare parts are available, and replacement parts work without the maker unlocking them.
Calm
Does not compete for your attention: no notifications, feeds or endless content. Does its job and gets out of the way.

Where to buy

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Survival checklist

What it survives, next to the smart one it replaces.
1
=SURVIVES(threat)Survives…
ThisCurta calculator
What it replacesSmart oneAsking Alexa
2
Power cut
TRUE
FALSE
3
Wi-Fi goes down
TRUE
FALSE
4
The company switches off its servers
TRUE
FALSE
5
Someone tries to hack it
TRUE
FALSE
6
A firmware update goes wrong
TRUE
FALSE
7
Twenty years from now
TRUE
FALSE
8
=COUNTIF(TRUE)Total
6 of 66/6
0 of 60/6

The smart one is the Asking Alexa.

Row 4

See it in the sheetIn the sheet
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A pepper grinder that does arithmetic.

Curta calculator

$1,000–2,000
Repairable · Calm
Curta calculator$1,000–2,000
Buy on eBay