It is a rectangular planter with a perforated or slotted cover going over top of it. Any kind of small garden can be created in the planter. You could have just grass, small flowers or, for less maintenance, a zen garden. This idea could be used in tables or bars for a balcony.

Specifics
The planter and cover are made of high quality acrylic. This is less likely to get too hot than stainless or glass.
There are holes in the bottom of the planter and wood surfaces for drainage.
The cover is removable and can be easily lifted off of the table or bar. This allows you to easily tend the garden.


The furniture and green wall are not central to this idea but I designed them in a minimalist Japanese style to go along with this rendition.

Credits
Thanks to zaphad1 for the sky photos.