Emulators are my personal favorite thing to do with homebrew. You can play all kinds of games on your 3DS, even ones never released for the 3DS or portable consoles in general. If your worried about the legal issues with emulators, the emulators themselves don't violate any laws, but the rom do unless you own the actual game yourself. So, let's go over some popular emulators, shall we?

 

Retroarch

 This is the big one. This is a suite of most of the best emulators, all in the same user interface. Retroarch is a modular emulator which lets you play games from tons of different consoles. There is a version for IOS, Android, the Wii, and many more. The 3DS version has a slightly smaller emulator collection due to homebrew being new, but there's still plenty of variety, including a PS1 emulator.

 You can get retroarch from the Libretro Website. Make sure you get the latest 3dsx nightly (there aren't any stable builds yet). To install it, simply choose the cores you want and put it in your 3DS folder. Here's a list of cores and what consoles they emulate:

 

2048 - 2048

Catsfc - SNES

Catsfc Plus (better sound, worse performance) - SNES

SNES9x - SNES

PocketSNES - Snes

Genesis Plus GX - Genesis/Mega Drive

Picodrive (worse accuracy, better speed) - Genesis/Mega Drive

Gambatte - Gameboy (Colour)

Nestopia - NES

FCEUmm - NES

QuickNES - NES

Mednafen - VB (Virtual Boy), PCE (TurboGrafx16), WSWAN (Wonderswan), NGP (Neo Geo Pocket)

Final Burn Alpha - Capcom Playsystem 1 & 2, and Neo Geo MVS

PCSX - Playstation (unplayable without <9.3 hax)

Mame - Arcade

NXengine - plays Cave Story (freeware version)

 

 

BlargSNES

 BlargSNES was the first SNES emulator on 3DS, and it still has a use. It is currently the fastest SNES emulator, and most games that run on it run full speed no problem.

 Unfortunately, BlargSNES has somewhat poor emulation accuracy behind the scenes, so while some games look and play fine, but others experience crashes and other annoying bugs. Another issue with blargSNES is the lack of special SNES chip support. The Super Nintendo lasted so many years because the cartridges contained chips which could enhance games, and made things like Star Fox possible. Yet another problem with BlargSNES (Do they ever end?) is the lack of extra features like save states and other cool features.

 As a result of all these issues, I wouldn't reccomend BlargSNES to n3DS users. If you have an o3DS, BlargSNES is still the fastest, so use it, but n3DS should just use Retroarch.