Here you can find my own Mathematica demonstrations (over 400) at the Wolfram site.
Introducing the Wolfram Demonstration Project with many of my works included: A Wolfram Demonstration Project bemutatása, ahol sok demonstrációm szrepel.
http://www.wolfram.com/broadcast/videos/discoverdemonstrations/
I talk about rediscovering the math of evereday life:
http://www.wolfram.com/products/mathematica/portraits/sandorkabai/
I talk about the role of Mathematica in education:
http://www.wolfram.com/broadcast/videos/userstories/sandorkabaiedu/
Mathematica models of star polyhedra on church tops:
http://www.employees.csbsju.edu/mwenninger/seteight/PAP209tarnai.pdf
LPSC2008/1022:
http://www.lpi.usra.edu/meetings/lpsc2008/pdf/1022.pdf
LPSC2008/1321:
http://www.lpi.usra.edu/meetings/lpsc2008/pdf/1321.pdf
LPSC2004/1081:
http://www.lpi.usra.edu/meetings/lpsc2004/pdf/1081.pdf
The Group of Six (A Hatok):
http://silver.szote.u-szeged.hu/~karsai/hatok/index.html
Presentation at a Hunveyor conference (in Hungarian)
http://media.mcse.hu/video/20080905/20080905e_Kabai_Sandor--Hunveyor_Mathematica_6.0_demonstraciok.