Every kid learned how to make a crystal glass “sing” at a dinner party, but now, you can solicit an accurate series of musical notes with this musical glassware from Luna & Curious. If you fill the glass with any liquid to up to the line marked “A” you will hear an accurate “A” note when rubbing the rim of the glass in concentric circles. At this rate, you can start your very own glassware musical band, but you’re going to need more than two hands.