Tandy

Ira Goldklang's TRS-80 Revived Pages
This page deals with the TRS-80: Emulators, Software, and Orch-80/85/90.
http://www.trs-80.com/

Jeff Vavasour's TRS-80 Emulation Page
Freeware TRS-80 Model I, TRS-80 CoCo 2, and TRS-80 CoCo 3 emulators.
http://www.vavasour.ca/jeff/trs80.html

NitrOS9
Yet another Coco 1/2/3 set of web pages by L. Curtis Boyle.
http://nitros9.lcurtisboyle.com/

Paul Robson's Emulator Pages
To build these you will need the shareware A86 assembler (easily available) and a 'C' Compiler. The programs were written in Borland's Turbo C 2.0 but should compile fairly easily under most compilers.
http://members.aol.com/autismuk/emu.html

Tand-Em
PCjr and Tandy 1000 emulator for 80386 (or higher)-based PCs.
http://www.oldskool.org/pc/tand-em/

TRS-80 Color Computer Software
TRS-80 ROM Images.
http://sites.mpc.com.br/ric/cp400/ecocmain.htm

Virtual T
An open source TRS-80 Model 100/102/200 emulator for Linux, MacOS X, and Windows.
http://sourceforge.net/projects/virtualt/

xtrs
An open source TRS-80 Model I/III/4 emulator for Unix.
http://www.tim-mann.org/xtrs.html