Tomato irrigation idea!
Puncture holes in an old water bottle and bury in the ground next to a growing tomato plant. The water will come out of the holes as needed (acting as a sort of drip irrigation) and the roots will be able to find the water on their own. Make sure to keep the opening of the water bottle above ground, to refill the bottle when it gets empty.
This method of watering is less harsh on the plants than watering from a hose or watering can, and allows for a continuous, slow drip, that can save you water!