There are some very good tips and tutorials on the use of nozzles in Corel Painter, Corel PhotoPaint, PaintShop Pro and Bryce.
Check out the 3D nozzles - Jungle Bundle - and Tubular Neon a must for use with a tablet.
If you thought that nozzles of flowers, trees, leaves and grass could only be used for natural scenes - and that's not your scene well...
They make a wonderful base for geometric designs.