High Quality (and Cheap) Airfoil Program!
FYI - A new version (2.10) of Profili / XFoil has just been released. One of the new features that caught my attention is the ability to analyze a turbulated airfoil. Haven't upgraded yet; should be interesting.
Hope the analysis of flapped airfoils has been cleaned-up (crashed every time I tried it in ver 2.03).