Water indoor or outdoor planters (especially hanging ones) with ice cubes. The ice melts slowly, giving the plant's roots a thorough watering, and the water doesn't drip everywhere.
Thrift-store glass globes can be topped with the light portions from solar stake-lights and placed throughout the garden as hanging or staked accent lights.
Setting inexpensive but attractive plastic beach balls on your outdoor furniture will keep unauthorized cats from lounging on it after hours.
Inexpensive beach balls can be tucked among foliage as garden ornaments. They're easy to replace if you change your accent colors.
Uses for an electric toothbrush:
Shop the Christmas aisles early for ornaments that can be used in the garden.
The top of a strawberry planter makes a great base for a garden ball or birdbath.