For the ice cream: Whisk together egg yolks, milk, sugar, and salt in top of a double boiler, then add vanilla bean. Cook over simmering water over medium heat, stirring constantly, until custard coats the back of a spoon. Remove from heat and cool. Discard vanilla bean, stir in cream, cover, and chill completely. Pour custard into ice cream maker and process according to manufacturer's instructions.
For the crêpes: Beat eggs, 3⁄4 cup water, milk, and 4 tbsp. of the butter in a medium bowl. Sift in flour and salt; mix well.
Lightly brush a small skillet with remaining 2 tbsp. butter and place over medium-high heat. When skillet is hot but not smoking, pour in 1⁄4 cup batter. Quickly lift skillet and swirl batter to make a thin crêpe. Cook until bubbles form on top and edges begin to brown. Turn with spatula and cook till golden.
Place a scoop of ice cream in the center of each crêpe and fold crêpe around it. Serve with fresh berries.