p-Value Calculator for the Student t-Test (Probability, p-value)
http://www.danielsoper.com/statcalc/calc08.aspx
Statsar statistics library
http://www.simplexar.com/Statsar/Product.aspx
Probability and Statistics for .NET v3.6
http://www.webcabcomponents.com/dotNET/dotnet/pss/
xtreme Optimization Numerical Libraries for .NET adds multivariate statistical analysis
http://www.extremeoptimization.com/
probability calculator
http://wareseeker.com/free-probability-calculator/
WebCab Probability and Statistics for .NET - .NET Component - V3.5 - Summary
http://www.componentsource.com/products/webcab-probability-statistics-net/summary.html