To Dazbo: You got there first - I remembered this looked helpful as a bit of an academic excercise and was going to post it as soon as I could remember where I'd seen it.

I have to agree with Anahata that trial and error is the most useful (and satisfying)way of finding chords - if you stick rigidly to what a Bmin7 is (or whatever) by reading it, you may never experiment and find that head-turner. Being an ear player, I often don't even know what the chord I'm playing is called and wouldn't remember if someone told me.

And finally to Fogie: Unless I'm missing something, adding a G note to Emin just makes it Emin all over again doesn't it? (E+G+B=Emin).

Cheers
Martin