(This is from a US perspective, so depending on where you're from ymmv)
IANAL but there are legit ways/reasons to offshore too. If you sell products outside the US, it might make sense to handle those international transactions from a offshore location instead of your US office. If you have significant IP, it might make sense for an offshore holding company to own the IP and lease it back to you. Of course, if you want to repatriate all of the income immediately, then there's not much you can do, but if you don't need the money as personal income, there's something to be said for letting your money grow in a more favorable tax environment until you do.
Also, depending on how mobile you are, if you establish residence outside of the country, you can get a 100kish income exclusion (double if married) plus a housing credit. Of course, it's a bit ridiculous that we have to pay tax if we live outside of the country. (Americans are almost uniquely hosed in that regard.) Of course, as a long term play, you could always renounce. Once enough people realize that you can shop for and evaluate countries (for business environment, quality of life, or whatever's important to you) just like any other major life decision, governments will need to compete to keep their best people, and that sounds like a good thing to me.