I designed this little 1" box as a test for the flexibility of our FilaOne™ Gray Carbon Nano-Tube Reinforced filament.

FilaOne™ Gray is an engineering grade filament with a fair number of desirable characteristics - it's quite strong, flexible and hydrophobic, and prints in the same temperature range as ABS.

https://proforma-3dprinting-store.myshopify.com/products/filaone-gray-advanced-composite-filament-samples

https://www.youtube.com/watch?v=5p3ZSVkygNw (Edit: fixed youtube link)

All in all it's a pretty successful test - the box can be unfolded and refolded indefinitely as long as you aren't working to tear the plastic.