Developer Rudi Rastelli just released PS3P PKG Ripper, a tool to extract PKG  PlayStation package files. The tool supports PSP game Files, PS3 game files, PS1/PS2 classics, DLC, Minis, Avatar/Theme PKG files. It also supports both Retail and Debug PKG files.

PS3P PKG Ripper Features

There exists many tools to do this kind of job, but PS3P PKG Ripper focuses on speed. Early tests show that PS3P PKG Ripper extracts a 2GB file in 1 minute, versus 12 minutes for other tools on the same machine. Yup, 12 times as fast. Icing on the cake, PS3P PKG Ripper comes with a GUI.

Rudi Rastelli followed his early release with PS3P PKG Ripper 1.1, which improves the GUI. The full feature list of PS3P PKG Ripper:

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*                     PS3P PKG Ripper V1.0                      *
* by Rudi Rastelli                                              *
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* Credits:                                                      *
* @mathieulh, @Mysis, @Ifcaro, No0bZiLLa                       *
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Features:
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- Supports PS3-, PSP-, PS1/PS2-Classic-, DLC-, Minis-, Avatar-, Theme-PKGs
- Supports Retail- and Debug-PKGs
- Supports PKGs of any size
- Extracts whole PKG
- Extracts selectable single files and/or directorys
- Progress Output (Overall/File)
- Lists contents of a PKG with size of files
- Changeable output directory
- Optimized for speed
- Optional GUI included
- Source code included
- Doesn't need any DLL's or any installed runtimes

Wanna say THX to
  @mathieulh, @Mysis - I've learned a lot from their sources
  @Ifcaro - From his 'PKGView' I've learned how to handle Debug-PKGs
  No0bZiLLa - For testing

Download PS3P PKG Ripper

you can download PS3P PKG Ripper here

source: Rudy Rastelli on PSX-Place, thanks to @Zecoxao