Milkshake-Style Purple Cow

1. Measure vanilla ice cream into your blender jar. If you don't have a countertop blender, use a narrow mixing bowl and employ an immersion-style "stick" blender to mix the ingredients.

2. Add frozen grape juice concentrate, allowing roughly 3 parts ice cream to 1 part frozen juice. If you're using an entire 5 ½- to 6-ounce can of frozen juice, a pint is just about exactly the right amount of ice cream.

3. Start your blender, mixing the ice cream and grape juice concentrate. Add milk slowly, until the mixture has a uniform color and the consistency of a thin milkshake.

4. Pour the drink into tall glasses and serve immediately.

Float-Style Purple Cow

1. Set out a tall glass for each drink you'll be serving, and provide both a straw and a long-handled parfait spoon for each.

2. Scoop 1 to 2 portions of vanilla ice cream into each glass, depending on its size.

3. Pour in enough Concord grape juice or grape soda to fill the glass. If you use soda, allow extra room for the beverage to foam up and then top up the glass after the froth subsides.

4. Serve the drinks immediately, before the ice cream melts.

Purple Cow Cocktail

1. Scoop a generous portion of ice into your cocktail shaker.

2. Measure enough vodka for one or more cocktails, as required. Add Concord grape juice and shake to mix well.

3. Divide the shaker's contents into individual highball glasses. If necessary, top each glass to the appropriate level with extra grape juice. The drink is ordinarily served without garnish, but if you wish you can split table grapes and decorate the rim with them.