VMware Fusion: Used for running Windows on Intel Macs. PCem 11 and 86box: A fairly interesting choice since it uses genuine BIOS for systems ranging from 8086 to Pentium, Which makes it great for running old software from those eras, I use it on modern Windows systems where Virtual PC is out of the question. Microsoft Virtual PC 2004-7 (Windows): Used for testing older Windows versions and software on the fly, Only works on Windows 2000-7. Microsoft Virtual PC (Mac): Interesting choice for running Windows versions up to XP on PowerPC Macs, I use 6.0.4 on OS 9 and plan on trying 7.1 on one of my OS X 10.4 machines. VisualBoyAdvance: The best one for all GameBoy generations from Classic/Color to Advance, Runs on Windows. Project 64 1.6: Pretty dated, But works nicely for emulating Nintendo 64 games on Windows. PCSX-Reloaded: A great Sony Playstation 1 Emulator for modern Windows and Mac OS X systems. Fusion: A Sega Genesis emulator that works great on older computers with Windows 9x. I know some of these have been mentioned here before, But I'll go ahead and list the emulators I mainly use here. I remember having to press a certain key just to go back to the ROM loading window.

Stellar - An Atari 2600 emulator which works smoothly but is entirely minimal (as in, no menu bar at the top).

People said that ZSNES was better but, I had a hard time trying to even load a ROM with it.

Snes9X - It might not be the best of all SNES emulators but, I felt more comfortable with it.

It is one emulator I would highly recommend.

Kega Fusion - Good support for all of Sega's systems, from the MegaDrive/Genesis to the Master System.VisualBoyAdvance - Pretty much everyone uses for all Gameboy systems, and was the second most-used of all.I think I can recall a Chinese version of this too. VirtuaNES - Another NES emulator, but this seemed better for the following reasons: the ability to quick save/load during gameplay and, has support for unusual mappers each time it is updated, mostly for these weird bootleg games floating about.FCEUltra - The NES emulator I used most often, and one of the best I had used.

When I used to do emulation gaming years ago, I used the following:

Snes emulator mac for ps1