vintagecalculators.com — Vintage Calculators Web Museum
vintagecalculators.com — some early electronic calculators which never went into production (at the bottom)
vintagecalculators.com — strange and interesting hand-held calculators ( Curta I ( vintagecalculators.com ) похож на ручную кофемолку! Kosmos I and Kosmos Astro ( vintagecalculators.com ) — biorhythm computer and astrological predictions! etc.)
Excellent source of interesting information!