From Ned at Devenish:
Piquette is a fizzy alcoholic drink made by adding water to the left over skins, pulp, and seeds of wine grapes after they've been pressed.  Here's a more in depth article.  The water soaks up more color and flavor and some left over sugar (sometimes people add a bit more unfermented juice or honey to boost the sugar) and you can then ferment it into a low alcohol naturally fizzy drink.  This is made by Sanctum in the lower Styria region of Slovenia from the must of Chardonnay grapes after they've pressed the juice off for their Chardonnay.  They soak the left over must for about 2 weeks before pressing the water/juice off and letting it ferment naturally in bottles.

Taste: fizzy and clean and straight forward. Lemon and green apple fruit and then a sort of apply sunny golden raisin mid palate. The finish has a nice little prickle from the bubbles and a taste that's a bit more savory and like ripe honey crisp apple. It's a really clean light fizzy wine drink. Basically think of pretty dry cider or like beer if beer was made from grapes. It's super easy to drink, refreshing, and clean. It's not super complex but that's not the point; this is thirst quenching, easy, great on it's own or with anything from spicy food to shell fish or lobster.... because it's basically like beer made from grapes.