Cabri Geometry, Geogebra and Generalized Functions

I came across Geogebra recently and loved it. Its free and Java based. The software is pretty intuitive and it has incited my curiosity in to the fascinating Geometry softwares. Unlike Maple and Matlab here you just sketch. Geogebra is fascinating because it generates the algebra on the side window. I have Cabri Geometry on my TI Voyage 200. The good thing is all geometry softwares look quite similar. If you know one its easier to migrate to other and you know what to expect from the other software. I now have the full user manual of Cabri Geometry and would explore more. I also have it installed on my computer and it works fine. It has macro facility so I am doubly excited.
On Fourier front I learned some more generalized functions and the book has one neat example on constructing Schwartz function. The amazing thing about generalized function is one can transfer the operation on generalized function to Schwartz function and Schwartz function are so benign they take anything that is thrown to them. Their derivative is again a Schwartz function and its a pretty neat theory.