Best way to protect my new commercial software.

[farsheed]

Thanks. But I ask this question technically, I mean I know nothing is
uncrackable and popular softwares are not well protected. But my
software is not that type and I don't want this specific software
popular.
It is some kind of in house tool and I want to copy protect it. this
is very complicated tool and not useful for
many people. indeed this is an animation manging tool I wrote for my
company. So if you have any idea that what is the best way to do it,
I'll appreciate that.