Have a look at these new experiments which violate
the impulse conservation "law":
http://www.wissenschaft-frontal.de/koerper.php?Lang=Eng
Regards, Stefan.
Here are the 2 experiments with Flash interface , so you can
try yourself and see the results:
http://www.wissenschaft-frontal.de/Versuch1.htm
http://www.wissenschaft-frontal.de/Versuch2.htm