Man... some of the "retro" things listed here... so many post-2000's... making me feel all old and stuff. ;-)

I have a Tandy Color Computer 3 (CoCo3) for which I have several games in both cartridge and 5.25" floppy form. Dungeons of Daggorath is really fun! https://en.wikipedia.org/wiki/Dungeons_of_Daggorath

I also have a Retron 5. It, itself, isn't retro, but it plays retro games, so I have several cartridges several retro consoles (NES, SNES, Genesis, GameBoy...) that I play on the Retron.

Sorry, I only started owning PC's when I was already 'old', in my thirties when Windows 98 was the current version. I missed out on all the real old retro things as I wasn't doing anything with computers and games at all in my twenties. I'm old too, just quite new to computers (but an ICT-course on the Tandy TRS-80 in highschool and playing games on my dad's Acorn BBC, but those were not owned by me).

A non-working 286 (my first PC), a Pentium IV with three different OSes (DOS/WinME/WinXP), several Olivetti Prodest PC1 (8086-compatible). My project for a personal museum of old machines is still way off in the future, unfortunately (I need a new job...).

Having and using a retro PC is an expensive hobby. Not the hardware itself - but a second desk, nice chair, and mostly room to put them somewhere.

Of course, that's from my perspective... living in the city.

For a while I kept my Athlon XP1700 as a second PC - but that thing was SO noisy.

Somewhere in the family garage, which is full of anything but cars, there is rumored to be a 70's pong console. Must check it out some day.

I am gonna receive an empty arcade cabinet that is SNK and gonna fix it up to put a pc inside. Gonna turn it into a GOG Metal Slug system and enjoy Infinite credits and 4k goodness. Eat that arcades of the 90s :)

I find restoring those things to have modern hardware is amazingly easy and fun. even emulators is easy to put for stuff like that.

I would love to have one of the old 8 bit computers from the early to mid eighties. Specifically the Tandy 1000EX, which happens to be the computer that I grew up using. Unfortunately many of those old computers have aged poorly, and it's next to impossible to find an original CRT monitor that goes with the system (at least one that's in good condition). I honestly wish that there was a company that did reproduction CRT's for all of the old 8 bit computers (Commodore, IBM, Tandy, etc). I'm also worried about having to buy all of the old games for that particular model. I guess you could use backup game files, but it kind of defeats the purpose of having an old machine. Part of the nostalgia is loading the game from an old disk. Although they were often unreliable.

I've my first 1993 PC to use pure DOS:

486DX2-66Mhz
8Mb RAM
2Gb Compact Flash as HD (I had to replace my old 250Mb cause it died, and bought an adapter CF2IDE)

And I kept also my second PC with multiboot OS Win98/Windows XP:

AMD K6-2 266Mhz
512Mb RAM
250Gb Disk
S3 Virge 8Mb VGA + 3DFX Diamond Monster 3D

I you don't find it, here's how to build a Pong console yourself (if you can read Dutch that is): https://tweakers.net/reviews/6820/bouw-een-pong-console-terug-naar-de-gameprehistorie.html

I did find a Commodore Monitor but unfortunately it had some power and display issues and I was unable to fix it, thankfully the Atari model I own has a really good composite picture so it looks great and a CRT TV.

As for finding games I have had moderate success on minding cartridges for it at good prices and many of these old systems do have mods or workarounds that allow you to play the games on the original hardware without having the physical media (which for some games are the only option since tapes and floppies are starting to fail)

None assembled, though if I scrounged around old parts I could probably build one with the following awesome retro pieces.

Geforce 6600 GT GFX card
Blazing fast 56/k dialup modem
Several various sticks of old SDRAM
SoundBlaster Audigy sound card
DXR2 DVD decoder board and Creative DVD-ROM drive (2 speed!)

A cheap online HD and CRT monitor later and I'd be doing some great spreadsheet action. Maybe even load up some Duke or Doom and sprite my way to back to 1999. I'd call it the Time Machine Action Machine. An hour later I'd get several file corrupts, followed by a disc that wouldn't load in the tray, and the CRT would cause a killer migraine that would make me have to turn everything off and lie on my bed in total darkness until the pain went away.

The computer I'm currently on is relatively old, 10+ years, and I'm upgrading soon.

I also have my grandparents' Windows XP Athlon machine.

I still have some papers and probably a few pens still usable oh and a pair of d20-s
good , throw the old crap out

At this point all my PCs are Retro Rigs, except for my work laptop which is like two years old, and can play e.g. Horizon Zero Dawn and The Witcher 3 passably, but not anything more demanding.

The next older PC I have is a 9 years old gaming laptop, still going strong, albeit not playing the latest games of course. Writing this message on it currently, and playing Icewind Dale 2 on it (on Linux of course, I am happy I don't have to boot to Windows just to play that game). It is a bit slower overall (in gaming) than that work laptop of mine, so it could manage to run e.g. The Witcher 3 passably.

Then I have several older laptops I've obtained somewhere, oldest one being an IBM ThinkPad T41 running both Windows XP and Windows 98SE. And I have one retro desktop that has some 1-core 64bit Pentium, or could have been some AMD Athlon CPU as well, not sure anymore...

Many of these have a true purpose for certain older games, e.g. that old desktop is probably the best rig for playing e.g. Mechwarrior 3 (which tends to have physics engine problems on too fast CPUs), and my eMachines laptop, which is running both Windows XP and Linux Mint, is great for playing "King Kong The Movie" game as that game does not work on anything newer than Windows XP due to its copy protection, but my other XP machines are too slow for that game, so that old laptop hits the sweet spot, running the game very smoothly and without issues with its copy protection.

I don't keep any real MS-DOS era PCs around anymore (with real MS-DOS mode, Soundblaster 16 ISA card, Roland SCC-1 + Roland CM-32L for MIDI music...) because nowadays I feel DOS games are better to be played in e.g. DOSBox, and I don't need the real MIDI sound cards anymore as Munt and VirtualMIDISynth do great job emulating them.

I seem to have obtained many of my older machines (laptops) by someone going to throw it away, and me thinking why would someone throw a perfectly working machine to trash when I can use it for something, install Linux on it etc. It is like someone throwing an old dog to the dumpster because they got a new higher-performance puppy, I still feel I could give a home to that old dog. So I am kinda keeping a kennel for old laptops, so to speak.

Oh and I also have a real (fat) PS2 console too, but I haven't switched it on for a year or two. I play my PS2 games on the PCSX2 emulator now, which by they way works better for me in Linux than in Windows (the Windows version has severe slowdown if I switch the emulator to fullscreen mode, while the Linux version runs at 100% speed both in windowed and fullscreen mode). Damn Linux is great for gaming!