IGN has all nine levels, from designers at Infinity Ward, Infinite Interactive, and other such prestigious studios, available for download and voting. It's really interesting to see what people who think about levels for a living do with the Bangai-O rule set. Harvey Smith, lead designer of Deus Ex, made an arena for super-annoying FastBots; Infinite's Steve Fawkner replicated the Atari classic Warlords.
All of the levels -- many of which tend toward the baroque -- are great, but our favorite is the simplest one: Shane Hensley's "Pinball Wizard," designed to imitate a pinball playfield. It looks stark, but explodes into bullets in a way that is startling even for Bangai-O.
Gallery: Bangai-O Spirits