The following are some interesting sites for anyone interested in learning about or using smoothing algorithms or computational geometry related issues.
Midpoint Smoothing Algorithm Tutorial
Tutorial on Hysteresis Smoothing for X-Monotonic Polygonal chains
USC Polygonal Represenations from Curves
Tutorial on the Approximation of a Polygonal chain using Imai & Iri algorithm
Godfried Toussaint's Computational Geometry Links
Image Processing Fundamentals - Algorithms
Computational Geometry basic tutorials