It all started when I was playing some Basshunter on the radio in the car, and Shawn commented that it sounded like Sibelius. We decided to think of with as many pairs as possible, and these are what we came up with:
| Sibelius | Basshunter |
| Shostakovich | Radiohead |
| Mozart | Eminem |
| Puccini | Madonna |
| Johann Strauss | Backstreet Boys |
| Richard Strauss | Pink Floyd |
| Berlioz | Marilyn Manson |
| Schumann | Nirvana |
| Mendelssohn | Weezer |
| Debussy | Postal Service |
| Ravel | Death Cab for Cutie |
| Pachelbel | Nickelback |
| Dvorak | Cake |
| Lizst | Michael Jackson |
| Wagner | Kanye West |
| Beethoven | The Beatles |
| Brahms | U2 |
| Vivaldi | Britney Spears |
| Bach | Christina Aguilera |
| Paginini | Liberacci |
If you can think of any other ones, add them in the comments!
Update: I added a few clips to demonstrate why I think some of these pairs are similar.