1 + 1 = 98
Isidoro Baroni was an early 20th century Italian amateur astronomer. Between 1900 and 1908 he published l'Astrofilo (the amateur astronomer), the first such popular astronomy magazine in the country.
I read some issues of l'Astrofilo, a publication with large pages and lovely illustrations featuring a vintage positivistic vibe. What caught my attention was an ad Baroni run for a subscription campaign. The slogan was “1 + 1 = 248”. At the time, l'Astrofilo had 124 subscribers. Baroni wrote that if every subscriber convinced another person to check out the magazine, the subscriber count might double.
If you like Practicing Google, it would be awesome if you could forward the newsletter to a friend or colleague. If each of you does it, the current 49 subscribers might grow to 98.