Thanks for moving this, Wolfden. So magic sysrq is actually not in Sabayon yet. I thought, I hadn't tried the correct keys on the notebook only.
If you are going to implement this feature in future, I think it would be great to make it optional via kerneloption ("cheatcode") in the bootloader-config at boottime (e.g. magicsysrq=on), so one can choose whether it is enabled or not by simply editing the line in menu.lst, since it is not always desirable to have these keys activated.