I like, not love, Metallica (I like them a lot better now that James sings), but I didn't get them until I saw them on Later... with Jools Holland. If you're not familiar with the show, it's a live music show with the guy that used to play keyboards for Squeeze. Five or six artists all line up in a room facing each other, and each plays a song or two and they rotate around the room. Once in a blue moon they'll show the other bands while one is playing, and they're usually tuning, or sitting on the drum riser, or very rarely strumming along quietly.
When Metallica was on, they played Enter Sandman as their second song, and EVERY other band was up on their feet, clapping, singing along, and more than one guitar player was playing along. I haven't seen that with any other artist - including Neil Diamond or Sir Paul. And it wasn't like the other artists were metalheads either. One was this cute singer songwriter from New Jersey (think a solo Susannah Hoffs) and she was rocking out like it was prom night. Awesome thing to see (and the band clearly fed on the energy; at that point James was the coolest man on the planet, and he knew it).