The file-sharing service known as Grokster has thrown in the towel in its battle against the recording industry, which has accused it of facilitating online piracy of copyrighted material. As part of the settlement, Grokster will halt distribution of its software entirely and pay $50 million in damages. It is also acknowledging on its website what everyone already knew: that trading copyrighted music and movies online is illegal. Like Napster before it, Grokster plans to reinvent itself as a legal music download service.