An offline crack for Diablo 3 would be like an offline crack for WoW. Anyone who actually wasn't trying to throw a trojan on your computer would not call it an offline crack.
It would be a emulated server that you'd have to run on your own machine.
Just to reiterate, an offline crack for Diablo 3 is not possible. Running your own emulated server is very possible, but will be a crap experience just like trying to run an emulated server for WoW.
We've decided to close this thread. Partially because it is discussing something that usually is forbidden here, even without a direct link, and also because it's getting pretty off topic in a lot of ways.