My first computer was a Radio Shack Color Computer 3 - 6809-based, running OS-9 Level II. It could run 32 processes at once, due to bank-switching a whole 1 Meg of memory.
After that, I got an AT&T 3b2, also known as a Convergent Safari. This was a Motorola 68010-based desktop.
Then, I graduated to a NeXT black&white "slab". I bought a used SPARCStation IPC in 1995, and put NetBSD 0.9 on it. I ran NetBSD on the IPC and a SPARCStation 10 until 2002.
I've been using Linux since 1997, starting with a DEC Alpha-based UDB, and downgrading to a x86 PC in 2002.
I run Arch linux, on my server and my laptop.