It Might Be NES

It Might be NES (imbNES) is a Nintendo Entertainment System (NES) emulator for the Sony PlayStation. It allows NES games to be played on a Sony PlayStation console.

It Might be NES was originally written by Allan Blomquist sometime around 2000, and updated for several years thereafter. The last version released by Blomquist was 1.3.3-WIP1.

Due to a series of circumstances, the project was discontinued.
It was, at that point, a dead-end, since the source code for the project was not public. In 2008, the original author released source code for version 1.3.2, under the GPL license on his website, as he was no longer planning to work on it due to having moved on, so that an interested person could start to make improvements to the emulator.
Unfortunately nobody started to work again on the emulator and the emulator sat unmaintained until 2015, until being picked up again.
A note: source code for 1.3.3-WIP1 was never released, as it was probably lost.

The emulator supports mappers 0, 1, 2, 3, 4, 7, 9, 10, 11, 33, 34, 38, 66, 70, 71, 79, 87, 140, 180 and 185. Not all games are guaranteed to work correctly, and some games may have graphical glitches.