FLEX-ES:
System/390 on Intel-based servers.
http://www.funsoft.com/
Soft390:
System/390 on IA64-based servers.
http://www.platform-solutions.com
Hercules:
An open-source emulator of S/370 and ESA/390 which runs under Linux
on a Pentium PC.
http://www.conmicro.cx/hercules/
Your Private Mainframe:
Introduction and links about the Intel-based Hercules mainframe
emulator, as well as an MVT tutorial and MVS 3.8 binaries and
add-ons.
http://www.schaefernet.de/hercules/
ThinkPad FLEX-ES:
IBM information concerning running a mainframe on an Intel-based
ThinkPad portable PC using the FLEX-ES emulator.
http://www.developer.ibm.com/welcome/s390/thinkpadefs.html
Hercules/390: the New Users Documentation Effort:
A volunteer effort by many authors to create a Documentation for the
Hercules emulator, coordinated by Cory Hamasaki, divided into
Primary, Non-Install and Advanced topics.
http://www.kiyoinc.com/hercdoc.html
Running Classic Operating Systems with Hercules:
A presentation at SHARE 97 by Jay Maynard of Global MAINTECH Corp.
Looks in detail at OS/360, VM/370 and MVS Version 3.8. [PDF]
http://www.share.org/proceedings/sh97/data/S2881.PDF