Thanks all, particularly lasseaagren. This looks very interesting and while I don't know Python, it seems easy enough to read.

I would love to say that I'll give this a go this evening, but unfortunately I have just broken the screen of my N900 - argh. What's worse: I live in Canada where Nokia "do not sell that model", and so apparently I will have to send my phone to the US for repair and I will need a US address for the purpose.

Look forward to giving this a try... eventually