The defining requirement for my first ever notebook (circa 1991) was that it had to be able to run the One True Emacs. That was met by a Toshiba T1800 w/4 MiB

The defining requirement for my first ever notebook (circa 1991) was that it had to be able to run the One True Emacs. That was met by a Toshiba T1800 w/4 MiB 386/sx @ 16 MHz, running a very early Slackware Linux. Wasn’t powerful enough to run X (in practice), but having Emacs means I can be productive. It still sets the lower bar for what I consider useful, but indeed, 2nd best thing is a terminal into a computer running emacs.