Sega Toys just introduced a weird new music gadget in Japan dubbed LIVEDREAM. LIVEDREAM resembles a Rockband stage with drums, keyboard, guitar, bass and light system.

You can choose from a pre-set list of tracks including classics like Purple Haze and Smoke On The Water, that LIVEDREAM should "perform". You can add and remove the instruments and LIVEDREAM would start or respectively stop playing that instrument automatically.
A demo video on the Sega site reveals that LIVEDREAM plays those classic rock songs as you would hear them played on a cheap Casio keyboard. You can choose between a Rock Band LIVEDREAM system and a Jazz Band version.
The mini band stage measures 445×210×245mm.
Via this Sega Toys page (Japanese).