Hardware Information
The Sun System Handbook, formerly known as the Field Engineer Handbook.

The Sun Hardware Reference:

Written by James Birdsall, this is the ultimate reference (although dated) for new owners of Sun hardware. Print it out and keep a copy handy.
Part 1 – Overview of the CPU / Chassis
Part 2 – Frequently Asked Questions
Part 3 – Boards
Part 4 – Boards (continued)
Part 5 – Keyboards/Disks/Mice/Monitors/Etc.
Part 6 – Appendices
Part 7 – Appendices (continued)

Older Hardware Info:
Sun E10K “StarFire-at-home” FAQ by Tonu Samuel
Linux on Sun E10K pages by Tonu Samuel
Ross HyperSPARC info (in German)
The Sun3 Archive
Peter’s Sun-3 Zoo
Sun 3/160 Technical Info by TechRat.
Old Sun Hardware Picture Guide by TechRat.
More Sun Pictures by Marc Sebastian Pelzer

Informational Documents hosted by SunHELP:

The Rough Guide to MBus Modules by Mike Spooner
FixSolaris! – a guide to securing a Solaris installation, by Christopher Petro.
Frequently Asked Questions about Buying an Old Sun System by Brian Brush
Operating a SPARCstation ELC as a Headless Server by der Mouse

ASCII “dumb” Terminal Resources:
Video Terminal Information (massive!) by Richard Shuford

Console Management:
ConServer – a software-based multi-port serial console server. Based on original work by Tom Fine and Purdue University.
Tom Fine’s original Console Server code
Purdue’s version of Tom’s Console Server code
The Greater Scroll of Console Knowledge
Stokely’s UNIX Serial Port Resources

Other Hardware Documentation:

Just The Facts about Sun systems from SunSITE at the University of Alberta