Trofast. Cool alternate use of the storage box and fun to do if you still have snow in your backyard.
"During the last snowstorm we built an igloo in the front yard using Trofast storage buckets as block molds. It turned out really well actually, the only downside is that it was so very temporary, lasting 5 days before the rain turned it into a small sad pile of snow. But while it lasted it was OUR IGLOO.
See details, pictures and a video of Remo's igloo.