Stevie Nicks is another rock performer who has repeatedly admitted her past drug use, specifically cocaine. But a persistent legend holds that the singer developed such a high tolerance for coke that she could only get high by ingesting it directly through her rectum in order to obtain the purest dose -- a rumor that has followed her around so much that she has specifically denied it in public.  Rod Stewart, on the other hand, bragged about doing it in his memoir.