Prep: Line a baking sheet or plate with parchment or wax paper.
Dip: Place a berry on a toothpick and dip in the yogurt. Set on the parchment paper in a single layer, and repeat until all the berries are dipped. Freeze until solid, about 1 hour.
Store: Eat immediately or transfer to an airtight container and store in the freezer.
Notes
Instead of blueberries, you could also use grapes, quartered strawberries, or virtually any bite-sized fruit (like diced mango, kiwi, or watermelon).