In no particular order of preference:
Hero System 5th ed (and if you want Fantasy, also get Fantasy Hero)
Rolemaster (Big monetary investment like D&D as much of the material is broken into seperate books)
Warhammer FRPG One of the few complete game systems, monsters, magic items, advanced classes (PrCs), spells, maps, setting and other goodies.
BESM: The original game system is simple yet fun. The Tri-Stat book I've heard eliminates a lot of the anime flavor for pure mechanical goodness.