As I said last month, if you're aren't absolutely certain that your heir under your state law is who you want to inherit your estate, you must make a will (and if you have children, you must make a will regardless).
Now, Neil Gaiman offers a sample will for authors with specific provisions for creative works. I can't vouch for its provisions, as it's not a wrinkle in estate law that I studied, but if you have intellectual property to dispose of, take a look at it, run it by an attorney in your state, and make a will.
My older post was prompted by a suspicion, based on almost no evidence, that John M. Ford hadn't left an enforceable will; I'm sorry to see that this seems to be the case.