Big fan of all of computer history but especially '90s to early 2000s machines. There's definitely some element of nostalgia to that since it's what I grew up on — System 7 at school, Windows 98 on the family PC, and various DOS/Win3/Win95 on my hand-me-down personal 486.
I also feel like that's the point when computers became recognizably modern and where the progression of technology stopped being entirely in my best interest, like the emergence of spyware which used to be rare enough to deserve its own term but is now just literally everything all the time. I love researching the evolutionary dead ends of computing as inspo for my personal projects, because there are so many cool ideas lost in products that didn't make it for marketplace and/or monopoly reasons.
The machine I've been spending the most time on lately is a HITACHI FLORA 270HX NW5, 900Mhz PentiumⅢ which is actually ACER OEM in disguise: https://www.hitachi.co.jp/Prod/comp/OSD/pc/flora/prod/oldmod...
Pixx:
— https://i.imgur.com/chwdeJT.jpeg https://i.imgur.com/N9sFQYZ.jpeg (I have two of them, using the other as the stand there lol)
— https://i.imgur.com/LEBbY9x.jpeg https://i.imgur.com/BODkAVB.jpeg
The Nicad battery still works!