Question: how to install flashplayer plugin in Sabayon of Gentoo ? 
Answer :
The adobeflash player is the most known stable package. install it with :
emerge -av adobe-flash
You can see more about these packages from this link
Are you behind 64bit system ? No problem you can still using the plugins of 32bit system
Install first nspluginwrapper with:
emerge -av www-plugins/nspluginwrapper
nspluginwrapper –verbose –install /usr/lib32/nsbrowser/plugins/libflashplayer.so
If you need pure 64bit system then just chang the lib32 with lib64
{module user9-footer}
