Yet this method still needs two units of PS3 (CFW & OFW) and this is very old way, do not OMG me!
Also see my Listing Of Working PS3 CFW Games on PlayStation 3 OFW.
1. download this UNLOCK c00.rar
2. install it to PS3 CFW
3. install any c00 games PKG, and i'm sure it will run obviously.