Built in music lessons.

An APPLAUSE sign that automatically lights up and cues the audience at the end of each song.

Larger drum symbols on the TOTL 'Pro' models.

In addition to pitch correction, also NOTE and CHORD correction.

Built in drink coasters.

Portable urinal that drops down from bottom of keyboard.

Built-in pop-up tip jar with fake start-up money.

Pop-up TV screen (for built-in DVD player) to watch while the keyboard entertains the audience. Porn movies optional, or, if Yamaha, could study PSR tutorial during the performance.

If Audya or MS, built-in toolkit and copy of schematics (and OS reload instructions).

Chord Sequencer (for the one person that will use it ).

OISAC for a logo (that's Casio spelled backwards).

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