Two years ago, I had a coworker give me a complete Power Mac G4 Cube setup with the original flat panel monitor, stock speakers, etc.
Unfortunately, I was never a classic Mac fan, and ended up giving the setup away to an enthusiast after it gathered dust in my basement for a few months. Odds are good that I made a big mistake...
I have had some nice stuff donated by co-workers as well. The G4 stuff seems all over the place price wise.
My story with old macs is a long one. We always had PC compatible stuff at our house, and I learned DOS at a young age, but our schools always had macs. I got to use Apple //e computers in elementary school, 68k Macs later on, and PPC macs in the late 90s. I went to a school for a while where it was a new school, and they had very limited IT staff. The teachers basically let me care for the classroom macs when I was in middle school.
I had quite a nice collection going by my late teens. I always worked and thrifted and bargained to get what I had. When I was 20, I was saving to finish college, and went to New Orleans where I worked as a security guard at several FEMA parks. When I got home I found out my parents were selling my childhood home and "would prefer I not come with them." I had to take my college savings toward a very small apartment and found a minimum wage job for some time until I got a job as a cable installer. During this time my parents apparently auctioned off most of my computers, including essentially my whole mac collection, behind my back. (I know it sucks. Thankfully, I'm blessed with great in-laws).
Fast forward about 10 years from then, I told the story to some co-workers and immediately had a PPC 7500 donated to me with a G3 upgrade card, followed by a G4 CRT emac. Between craigslist and ebay I rescued some other macs, namely a pismo 500, a mac SE, and another power macintosh 7500 that came with the legendary AEKII, worth more than I paid for the whole auction. Sometimes it's funny how the universe works out.
Anyway, below are some pictures of the Mac SE I rescued from craigslist. It was absolutely filthy and reeked of farms and cigarette smoke. I wish I had proper before pictures but I always suck at taking photos during restoration.
For the restoration I did effectively a full tear down. All PCBs were recapped: analog board (chassis for us arcade folks), logic board, and power supply all got fresh caps. A few tweaks on the monitor and it looked great.
The original 20MB HDD was still intact, and had a users data from the early 90s on it. I tossed that, as a SCSI2SD made much more sense. The final config ended up being an internal SCSI2SD with multiple virtual hard disks, booting OS6 and OS7. The machine is capable of appletalk serial connection to my powermac 7500, and the powermac has internet access and file sharing capability. In short I can access a file share on one of my internet connected macs, and that's pretty sweet for an old 68k mac.
I also set up a 2nd SCSI2SD as a virtual zip drive, with hot swappable SD cards. It didn't end up being a necessity for me but I documented the config over on the 68kmla forums. It was really cool, as using the normal zip100 driver and device ID's I could set 1GB volumes in scsi2sd config and they worked fine. The tl;dr was hot swappable 1GB micro SD cards which appear to macos as zip disks.