SSF

SSF by Shima is currently your first, best and only REAL emulator out there for the Sega Saturn hardware. It runs many commercial games at a playable level, and frequently can do so with very minor glitches or seemingly none at all!

However to all things there are downsides. If you want the highest compatibility with games, you will need a fairly powerful machine to run it (The developer's reference machines are a Core i5, i7 and Phenom II X6, with a minimum 3 GB of RAM). The configuration and menus are a bit confusing, but veteran emulator users should be able to figure it out with some trial and error (and maybe some searching). SSF isn't as feature rich as emulators for other systems, like Snes9x, so if you're looking for features like Netplay or cheats, you will be disappointed. SSF is also a closed source Windows-only program. Another difficulty is the language barrier - Shima's site and twitter feed are in Japanese, though there are fan sites and emulator communities you can go to for assistance.

While there are other Saturn other emulators out there (Satourne, which hasn't been updated since 2006, and Yabause, which is open-source doesn't have SSF's compatibility yet), SSF beats all of them in compatibility and accuracy. If you missed out on the Sega Saturn back in 1995, or just want to play some classic titles for the platform, SSF is the best option out there for now.