This takes us back to fireflies in a jar with holes poked in the lid. It's the Sun Jar by Tobias Wong. It's a sandblasted glass jar with solar-powered LED lights inside. Leave it in the daylight and it'll emit a soft warm glow at night.
As they said over at Charles and Marie, where you can purchase the jar:
It is a great little idea for an outdoor summer dinner, where you have the jars scattered around the table, or an evening at the beach where they will provide just the right amount of light, or as garden illumination, just position them at strategic points in your garden or rooftop terrace or balcony – they work equally well in either location.
Check out AT:LA to make it yourself.