Did this with the Computers Club Drawing Society software but took it down because it's so much like other things I've posted on the site recently. Was suddenly noticing quite a bit of latency in drawing lines onscreen there. In addition to the lag the curves kept trying to straighten out as I drew them. In this drawing I tried to "roll with it" and let the bush be spiky and geometric. I hope this delay/glitch is a slow network and not some new issue with Windows 7, my tablet, or some other aspect of my personal decaying computational environment.
Update: The latency issue was caused by a pen/tablet feature I thought I turned off, called "Flicks" -- you are supposed to be able to control navigation using flicks of the pen -- whatever.