I often see a guy playing who does a mean Sweet Child of Mine on accordian. He even did Led Zep's Rock & Roll the last time I saw him, (in a cajun style, if you must know.)

All good stuff.

Putting it the other way, back in the late '70s, I went to Sheffield City Hall to see a band, (possibly Judas Priest or Black Sabbath,) and the support band were an Irish rock band called Mamas Boys. Jigs & reels in a pure heavy rock style. Magic, real magic.

Ever since Dave Burland started singing Boomtown Rats "I don't Like Mondays" saying it is a ruddy good folk song, (and the song was in the charts at the time) I looked at what could, would and does cross boundaries. I then noted Bill Caddick borrowing a Russian tune that Tchaikovsky either wrote or collected and realised...

There is a word called music. It describes an abstract aural art. Let's leave classification at that. I do. All my iTunes collection has been altered so the genre for everything is Music, rather than folk, celtic, classical, opera, rock, pop etc.

Interesting thread though. Some decent replies.