Well, I'd not go so far as to call myself an L-systems expert, though I've played with the type a lot over the last 4 years. As I understand them, L-systems can be made of geometrical shapes which are themselves made of straight line segments; and by using the second method of programming them in Fractint - d instead of f, Angles explicitly specified, etc. - any angle, including non-integer ones, is possible. (Please someone correct me if I'm wrong.) But regarding the M-set, I checked out its shape a while ago as merely a set of 1 cardioid and infinite circles. Turns out that they aren't quite circles after all, and they aren't even off circularity by the same amount in each case. So that complicates things. Also, the M-set and current L-systems programming seem to be SO different from each other that I despair of the latter ever rendering the former - at least, as L-systems are used in Fractint at the moment. I think that adding curves to L-systems would not help this, though it would still obviously hugely extend the possibilities in other ways. Tony Hanmer