Welll... 'might as well get this thread goin'

For me, it wasn't a riff so much as the chord progression for "That's The Way" on Led Zeppelin's third album.

That was the first time I set up an acoustic 12-string for an open tuning. The results were orgasmic!

LedZep did a lot of acoustic material, and from them I learned that you don't have to blow the windows out of the venue, to make music that will stay with your audience long after the show is over. Before that, I was just another string-slingin' fool trying play faster'n'louder than any other fool.

I play bluesey jazz these days. I don't think it's a coincidence that Led Zeppelin music has a lot of blues in it.