This screenshot has been taken while listening to the 250th episode of "State of Trance" by Armin Van Buuren. So yeah, I'm an avid trance music fan so there's my little tribute.

This screenshot, besides the cool "State of Trance" wallpaper, shows beep-media-player with a breeder_unit skin, a transparent xfce terminal and the rest is GNOME with Tango icons.