Simple, clever, and effective

Stacking trays at NetCAD, Canadian Blood Services, Vancouver, BC

I love clever little inventions. These stacking trays are used to hold donations bags at the blood donation clinic. The donation bags can't be squashed.

These trays can be stacked two ways. When the colours match, like the top two trays, they sit down inside one another. In this configuration additional trays only add about an inch (2.5 cms) to the overall height of the stack. However, when the colours don't match, like the bottom two trays, the contents of the tray are given some breathing room.

Clever and well designed. This is the sort of simple solution that makes me wish I'd thought of it.