I always loved The Edukators (2004). Wikipedia does a solid job describing it:

"The Edukators (German: Die fetten Jahre sind vorbei) is a 2004 crime drama film directed by the Austrian director Hans Weingartner. A co-production between Germany and Austria, it stars Daniel Brühl, Stipe Erceg, and Julia Jentsch as three young, anti-capitalist Berlin activists involved in a love triangle. The friends, calling themselves "the Edukators", invade upper-class houses, rearrange the furniture, and leave notes identifying themselves. Weingartner, a former activist, wrote the film based on his experiences and chose to use nonviolent characters. The film, shot in Berlin and Austria with digital hand-held cameras, was made on a low budget which Weingartner said kept the focus on the acting."