Possible Clues:

• Beyoncé, since 2002
• It's just him or her on stage
• Taylor Swift, typically
• One-man band, e.g
• Stand-up routine, usually
• Ozzy Osbourne became one in 1979
• Ex-band member, maybe
• Ex-band member, perhaps
• Typical comedy club performance
• Something David Copperfield has that Penn and Teller don't