I'm working on getting an old Sun Ultra 5 workstation up and running. See here: https://en.wikipedia.org/wiki/Ultra_5/10 if you don't know of it.

I have no monitor, mouse or keyboard right now, so I basically can't do anything with it. I got some serial cables and a Sun keyboard and mouse for cheap on eBay, hopefully when I get those I can get something working. It has CD, floppy drives and an Ethernet port, so it shouldn't be too hard to get it working (if everything works) once I have a serial cable and can use my laptop as a terminal. Believe it or not, my old laptop has a serial port. I might pick up a monitor that works at a garage sale at some point, so I can use X, but performance will probably be lacking.

I remember it having Solaris on it, I don't remember the CPU frequency (could be anywhere from like 200-400 MHz). I plan to play around with Solaris but ultimately install OpenBSD on it and use it for testing ports: the byte order on sparc64 is reversed, and there are a few platform quirks that makes it good for catching assumptions. Everyone nowadays seems to assume they're on a GNU, Linux, amd64, relatively new, fast PC with lots of RAM.

Expect me to send you patches to fix your software on OpenBSD/sparc64 :)