Put two of them end to end forming a standing/raised planter box for a home garden or flower bed.....put two of them end to end and seal the middle and make a fish pond by making it level with the ground or build a wall around it and have a standing fish pond......put two of them together and seal the middle and add a water pump and make a waterfall for the yard...since I don't know what "hdpe" stands for that is all I can think of besides putting them on amazon or ebaymotors.....