The berserk command allows you go into (and come out of) a berserker rage.
Only barbarians may use the berserker rage. The berserker rage multiplies
your combat bonus by a factor of 2.5 (sysop configureable), but you burn 
more fatigue (sturdiness and restoration don't help).

To enter a rage, simply type "berserk". To exit the rage, type "berserk"
again.
