MultiEmulator is described as 'free Tool for Windows that supports a wide range of Emulators / video games with a high level of compatibility and functionality' and is a Game Emulator in the Gaming Software category. There are seven alternatives to MultiEmulator for Windows, Linux, Mac, Android and iPhone. The best alternative is PCSX2, which is both free and Open Source. Other great apps like MultiEmulator are OpenEmu (Free, Open Source), RPCS3 (Free, Open Source), BizHawk (Free, Open Source) and Play! PS2 Emulator (Free, Open Source).
Open Emu is an open source project to bring game emulation to OS X as a first class citizen, leveraging modern OS X technologies such as Cocoa, Core Animation and Quartz, and 3rd party libraries like Sparkle for auto-updating.
BizHawk is a multi-system emulator designed predominantly around the production of Tool Assisted Speedruns (TAS). BizHawk focuses on core accuracy and power user tools while still being an easy-to-use emulator for casual gaming.
Play! is a portable PlayStation2 emulator. The focus of the project is on making PlayStation2 emulation easy and accessible. Just pop in your favorite game's disc and have fun! No BIOS required. Play! is an high-level emulator.