Wow... Messing with the settings can make a BIG difference to the time it takes to calculate stuff... My little animation runs for about 80 frames. Before I tweaked the settings, it took just under an hour or so to calculate the dynamics of the dress and hair. Last night I made some changes to the cloth room settings, and set it calculating, and went to bed. This morning, it's only on frame 14!! That's not rendering, that's just calculating dynamics! I hope this means I'm doing something badly wrong (as I suspect is the case, from Chanson's message in this thread), because otherwise I need a computer that runs at 100-200 Gigahertz instead of the 1.6 I've got at the moment!