Die Spitz - saw them open for another band a week or two ago and they are very talented and pretty young to be so talented IMO.
I've seen the drummer and guitar player switch out - and they switch out the lead singer duties between them as well - pretty unusual in my experience. The "primary" lead singer also plays guitar - so its not like she is just playing tambourine or something like Davy Jones.
Anyway if you like Punk, Grunge or Riot Grrl worth checking out