Apple II
AppleWorks on the Apple II
1984 not only brought us the Mac, it brought us an 8-bit app that made it easy to resist purchasing a Mac.
database
database
dBASE on the Kaypro II
CP/M and dBASE were industry giants with everything to lose, and they did. For a time they were the power couple to beat.
database
Superbase on the Commodore 64
Into the 80s, the promise of a "paperless office" sat always out of reach, but definitely almost here, so long as your office never grows past 1999