Cheers, Stu. I've got this wee sythesiser thing - a Korg Kaossilator, which replaces the keyboard with a mode-friendly dynamic X-Y pad - for live loops beats & drones. The crwth & kaossilator were recorded in real time, and I added the bass ostinato afterwards.

Here's a visual demonstration on YouTube:

http://www.youtube.com/watch?v=MynD0nTYWfc