State Machine Tool in Silverlight
I have made a "SM Tool" during the last summer. It is a program, which allows you to work and play with Finite-state machines. It was my credit work on Advanced programming for .NET.
C# and .NET
Lightweight fast matrix class in C# (Strassen algorithm, LU decomposition)
This is lightweight (19 kB) matirx class written in C#, that includes basic matrix operations.