MIDI Sight Reader is an online music application (mupplet) inspired by its predecessor, the original MidiFlashCard system. The application scrolls both piano notes and guitar tablature. Notes are played for audio confirmation as they pass under the centerline on the window. The scrolling staffs drive a keyboard model and a guitar neck model. The guitar and keyboard can drive each other as well, for interactive exploration of the correspondence between the two instruments. The 3 components, staff, keyboard and guitar, can be independently added and removed from the top down, so many combinations of layout can be achieved.