Project64 (PJ64 for short) is a free and open-source Nintendo 64 (N64) game console emulator for Windows platform. It has very high game compatibility and dispenses with the BIOS files, allows users to play the classic N64 games on the computer with ease.

VisualBoyAdvance (VBA for short) is the number one, the most successful and most popular handheld emulator in the history of Game Boy Advance emulation. It is also one of the best video game emulators, and it's completely free and open source.

ZSNES is an open source Super Nintendo Entertainment System (SNES) /Super Famicom (SFC) video game emulator for PC users, it has very high compatibility and supports Windows, Linux, FreeBSD, and MS-DOS.

Gens32 Surreal is the advanced, modified edition of the classic Gens emulator for the 16-bit video game consoles SEGA Genesis, Mega-Drive (MD), Sega-CD, Mega-CD and 32X systems, based on Gens emulator but added lots of features. It was developed by DarkDancer from Germany.

Happy Chick Emulator (also called 小鸡模拟器) is a free versatile emulator APP from China I recently found. It makes playing video games on Android or iPhone never been easier. It not only has built in a variety of excellent emulators, we can also download any game ROM with one-click, all of which let us fondle admiringly.