As many a child has realized during a fancy dinner, crystal glasses make a ringing noise when a bored diner runs a wet finger around the rim. Similarly to blowing into a beer bottle, the act usually only produces one note, but with a little strategy, you can make a whole song. These special crystal wine glasses from UncommonGoods have markings on them to show different notes. Simply pour enough wine (or grape juice) to the indicated lines to produce the right notes.
via Mental Floss
Image: UncommonGoods