1. In a bowl, combine oil, 30 mL (2 tablespoons) maple syrup, 30 mL (2 tablespoons) balsamic vinegar and 15 mL (1 tablespoon) thyme. Reserve.
2. Using a wooden skewer, prick tomatoes so that they soak up marinade. Place tomatoes, honeydew melon and cantaloupe in the marinade. Stir and allow to sit for 1 hour in the fridge.
3. In the meantime, soak 8 wooden skewers in water. Reserve.
4. Pour remaining maple syrup and balsamic vinegar into a small saucepan. Heat over medium-high heat until the mixture is syrupy and reduced by two-thirds. Reserve.
5. Thread a cherry tomato, a honeydew cube, another tomato and a cantaloupe cube onto a skewer, and end with another tomato. Repeat for the other skewers.
6. Heat barbecue grill to medium heat. Cook skewers for about 2 minutes on each side, or until fruit is hot but still firm.
7. Serve by spooning balsamic vinegar syrup over skewers and sprinkling with fresh thyme. Serve with grilled fish.

VARIATION: For a change of flavours, replace maple syrup by honey, and balsamic vinegar by white wine vinegar.