WordNet (r) 3.0 (2006):

ball of fire
    n 1: a highly energetic and indefatigable person [syn:
         powerhouse, human dynamo, ball of fire, fireball]
    2: someone whose career progresses rapidly [syn: go-getter,
       whizz-kid, whiz-kid, ball of fire]

Moby Thesaurus II by Grady Ward, 1.0:

22 Moby Thesaurus words for "ball of fire":
   activist, beaver, big-time operator, bustler, busy bee, doer,
   eager beaver, enthusiast, go-getter, human dynamo, hustler,
   live wire, man of action, man of deeds, militant, new broom,
   operator, political activist, powerhouse, take-charge guy,
   wheeler-dealer, winner