Reuse juice cartons (tetrapak) as a mini wall shelf.
Just apply some glue on two adjacent sides and stick it to a wall corner (see pictures).
Step 1: Wash the Carton
Clean up the inside of carton with water or any cleaning agent. This is to get rid of any juice inside the carton.
Step 2: Find a Wall Corner
Find a corner where you can fix your carton to make a shelf (see sample images above).
You should decide on the corner before the next step so that you know which sides to apply glue on.
Step 3: Apply Glue
Apply glue on two adjacent sides of the carton.
You may experiment with regular glue first and if it doesnt hold, use a better glue.
Step 4: Affix the Carton to the Wall
After you apply glue, affix the carton to the wall corner (see picture).
Hold it for a while so that the glue dries.
Step 5: Variations
You can try a one-side-glued variation on a flat wall instead of a corner.
You can also make a shelf kind of arrangement with on carton over another (with few inches gap in between)