In a blender or food processor, whirl milk, eggs, flour, and curry powder until smooth, scraping container sides as necessary. (Or in a bowl, whisk mixture until smooth.)
Place a 10-inch nonstick frying pan (7 1/2 to 8 in. across bottom) or crêpe pan over medium-high heat. When pan is hot, add about 1/4 teaspoon butter and swirl until melted. All at once, add about 1/4 cup batter and tilt pan in a circular motion to coat bottom evenly. Cook until crêpe is dry-looking on top and lightly browned on the bottom, 3/4 to 1 minute. Turn with a wide spatula and cook until other side is lightly speckled with brown, 20 to 30 seconds. Slide crêpe from pan onto a plate. Repeat to cook remaining crêpes, stacking on first (if making crêpes up to 3 days ahead, stack between sheets of waxed paper, wrap airtight, and chill; freeze to store longer).