My desktop is a cheap old Gateway DX4885-UB3A that I've upgraded with two 1TB hard drives. It has an i5-4430 processor. I've got it connected to an HP Pavilion 27xi 27-inch LED monitor which might have cost me more than the rest of the machine, but I think the extra screen real estate is worth it when I'm programming.

My laptop is an even older ThinkPad T410. It's a heavy, clunky brute by today's standards but it still runs like a champ and I don't use it more than once a week anyway.

Currently running MXLinux on both machines, but as I said in my own intro I'm thinking of going back to one of the BSD's -- if I can confirm that my scanner will work with them. (It's one of those flatbeds from Canon, whose support for open source platforms is abysmal.)

Oh, and I might as well mention my most ancient yet trustworthy piece of hardware: my HP LaserJet 4plus printer. I've had that thing since I don't know when and other than needing its rollers cleaned every couple of years has been extremely low maintenance. They don't make them like that any more, which is a shame.