8 ounces grape or cherry tomatoes, halved lengthwise (2 cups)
1/4 cup thinly sliced fresh basil
Special equipment: an adjustable-blade slicer with julienne cutter or a julienne peeler
Directions
Working with 1 zucchini at a time, cut lengthwise into very thin (julienne) strips with slicer, turning zucchini and avoiding core. Discard core.
Toss zucchini strips with 1 teaspoon salt and let drain in a colander set over a bowl, covered and chilled, 1 hour.
Gently squeeze handfuls of zucchini to remove excess water and pat dry with paper towels.
Cook corn in a small saucepan of boiling water until tender, about 3 minutes. Drain, then rinse under cold water and pat dry.
Whisk together lemon juice, sugar, pepper, and remaining 1/4 teaspoon salt in a large bowl, then add oil in a slow stream, whisking. Add zucchini, corn, tomatoes, and basil and toss well.