There are atleast two groups calling themselves Bang! (or Bang)

1) Bang! is an eurodance project from Germany.
It was produced by Ollie Stan, Teddy Delight, Petersman and Alex Selitsch
Bang! released the singles "You Know I know" (1994) and "Everybody, Everywhere" (1995).

2) Bang! is a UK happy hardcore act who wrote what is probably the biggest happycore anthem of the late-90s, "Shooting Star".
Nick Arnold and Jo James were the duo of Bang!. Jo James did the vocals on most tracks. Donna Grassie sings in "Cloudy Daze". Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.