The ink thing wouldn't work because then companies would have to pay more for ink, which they obviously don't want to do. The cost of extra plastic is nothing compared to the cost of extra ink.
They have the tea cup thing already, I saw it at Target the other day.
You could just use a knife for the corn contraption.
Just use a can opener. Costs like one dollar compared to the $40 it might cost.
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The only useful thing is the brush and the outlet.
