This is technically a bit of a spoiler for the book, but a) a lot of them are not in the book, and b) the book comes out in half a year, and we’ll all forget by then!
Let’s start!

@mwichary It was tragic that right about the time that Palm finally really figured out its smartphone OS and form factor, the company imploded because of the iPhone
The little butterfly keyboards always made sense to me - wish that there were a full-size one with the split keyboard layout because: Big Hands
@mwichary I had one like this for my Edge device, and it was surprisingly great.
Surprising, in that there was never an equivalent thing for iPhones.
I really feel like this should not have been an evolutionary dead end, but it very much was.
@mwichary this was TI's way of attempting to provide dedicated letter keys for programming while also evading American standardized tests' rules about what is considered an allowable "calculator" and what is an illegal "computer"
their later revision of this model has a rearranged keypad with the letter keys all together at the bottom, but notice that they're not in QWERTY order, one of the preconditions for being considered a "computer"
@mwichary wow! I just saw a video where Penn Jillette was wearing this exact watch!
https://youtube.com/clip/UgkxXw6obbMlEwgglS-DHq5chgFoogGZuTO7
55 seconds · Clipped by Brian Fitzpatrick · Original video "The Unpleasant World of Penn and Teller E01" by VHS Video vault