Not all heroes wear capes. Some wear surgical masks and scrubs.Dave Grohl paid tribute to one of the normal-size giants who walk among us when he Zoomed in for a surprise appearance Monday night on Jimmy Kimmel Live.The real surprise lay in wait for emergency and trauma nurse TJ Riley from Jacobi Medical Center in The Bronx, NY who has battled with COVID-19.Riley is also a big-time Foo Fighters fan.