Have you ever looked at someone with impossibly long, thick, and lustrous hair and wondered which piece of their genetic code was responsible for such wonder? Well, these days, there's a good chance those enviable locks have less to do with DNA and more to do with hair extensions. Once reserved for the Hollywood elite and those with insanely deep pockets, hair extensions of all varieties have become equally commonplace among A-listers and everyday folks alike. "They're not Hollywood's best-kept secret any longer," says Ted Gibson, legendary celebrity hairstylist and founder of his eponymous L.A. hair salon. "They're really versatile in application, and in a way, you can really be a different person by wearing extensions."