How can I encrypt JavaScript code so that it's not decryptable?

Question

I have some JavaScript code I need to encrypt, but I want to be sure no one can decrypt it.

What tools can I use to do this?

-- Edit --

Answer 1

There is no way to do that. You can obscure it and have some domain checking code in it. Or you could have it served with a server-side script that checks the referring domain.