Best Background Music for Tabletop Miniature Gaming
For Arcane Legions: Hans Zimmer, hands down. Que up some Hans Zimmer in GlooveShark, play all, and enjoy a night of thematic music for your epic conflicts! Actually, Hans Zimmer is probably the best background music for any tabletop miniature game, but maybe more for historical/fantasy themes like Warhammer Fantasy.
For Mechwarrior or sci-fi themed games (WH40k), the soundtrack for MechWarrior 2 (old computer game) is excellent. Lots of slow and heavy beat tracks that just exudes a 100-ton walking robot.
For Star Wars Miniatures: John William's Star Wars soundtracks of course!