JSPspEmu Git (2014/05/04) is released. JSPspEmu is a PSP emulator made using javascript (actually typescript). It will work with any modern browser. Though the first version work only works with Chrome (desktop and android). At this point it can run some demos.

JSPspEmu Git Changelog:
* - Added support for memorystick information
- pixelformat and unswizzling huge speedups
- Used blob instead of base64 to get image urls on browsers supporting it
- Added pspautotests submodule
- Added a new sample game
* - Implemented callbacks
- Small speed tunes
- Small fixed
- Some more scePower implementation
* - Fixed simple testasm.ts
- Added Math.sign and Math.rint
- Fixed MathFloat items
- Fixed fpu tests

Try online: JSPspEmu Git (2014/05/04)
Source: Here