A three-dimensional structure composed of pliable elements, comprising: a bottom panel (206, 300) with a longitudinal axis (208, 302) that serves as the bottom of the structure when in standard use, the bottom panel (206, 300) comprising: a first longitudinal side extending generally along the longitudinal axis (208, 302), wherein the first longitudinal side is not skewed more than 45 degrees parallel to the longitudinal axis (208, 302), a second longitudinal side extending generally along the longitudinal axis (208, 302), wherein the second longitudinal side is not skewed more than 45 degrees parallel to the longitudinal axis (208, 302), a first terminal bottom portion comprising at least a first edge segment, a second edge segment, and a third edge segment, wherein: a) the first edge segment extends from the first longitudinal side at a first inner angle, b) the second edge segment extends from the second longitudinal side at a second inner angle, and c) the third edge segment connects the first edge segment and the second edge segment; a first end panel (202, 400) with a vertical axis (204, 402) that serves as the end of the structure when in standard use, the first end panel (202, 400) comprising: a first vertical side extending generally along the vertical axis (204, 402), wherein the first vertical side is not skewed more than 45 degrees parallel to the vertical axis (204, 402), a second vertical side extending generally along the vertical axis (204, 402), wherein the second vertical side is not skewed more than 45 degrees parallel to the vertical axis (204, 402), and a terminal end portion comprising at least a first edge segment, a second edge segment, and a third edge segment, wherein the first edge segment, the second edge segment, and the third edge segment of the terminal end portion have substantially the same dimensions as the first edge segment, the second edge segment, and the third edge segment of the first terminal bottom portion, and further wherein: a) the first edge segment extends from the first vertical side at a first inner angle, b) the second edge segment extends from the second vertical side at a second inner angle, wherein the first inner angle and the second inner angle of the terminal end portion are congruent to the first inner angle and the second inner angle of the first terminal bottom portion, and c) the third edge segment connects the first edge segment and the second edge segment; and at least one affixing element joining the first edge segment of the first terminal bottom portion with the first edge segment of the terminal end portion, the second edge segment of the first terminal bottom portion with the second edge segment of the terminal end portion, and the third edge segment of the first terminal bottom portion with the third edge segment of the terminal end portion. a bottom panel (206, 300) with a longitudinal axis (208, 302) that serves as the bottom of the structure when in standard use, the bottom panel (206, 300) comprising: a first longitudinal side extending generally along the longitudinal axis (208, 302), wherein the first longitudinal side is not skewed more than 45 degrees parallel to the longitudinal axis (208, 302), a second longitudinal side extending generally along the longitudinal axis (208, 302), wherein the second longitudinal side is not skewed more than 45 degrees parallel to the longitudinal axis (208, 302), a first terminal bottom portion comprising at least a first edge segment, a second edge segment, and a third edge segment, wherein: a) the first edge segment extends from the first longitudinal side at a first inner angle, b) the second edge segment extends from the second longitudinal side at a second inner angle, and c) the third edge segment connects the first edge segment and the second edge segment; a first end panel (202, 400) with a vertical axis (204, 402) that serves as the end of the structure when in standard use, the first end panel (202, 400) comprising: a first vertical side extending generally along the vertical axis (204, 402), wherein the first vertical side is not skewed more than 45 degrees parallel to the vertical axis (204, 402), a second vertical side extending generally along the vertical axis (204, 402), wherein the second vertical side is not skewed more than 45 degrees parallel to the vertical axis (204, 402), and a terminal end portion comprising at least a first edge segment, a second edge segment, and a third edge segment, wherein the first edge segment, the second edge segment, and the third edge segment of the terminal end portion have substantially the same dimensions as the first edge segment, the second edge segment, and the third edge segment of the first terminal bottom portion, and further wherein: a) the first edge segment extends from the first vertical side at a first inner angle, b) the second edge segment extends from the second vertical side at a second inner angle, wherein the first inner angle and the second inner angle of the terminal end portion are congruent to the first inner angle and the second inner angle of the first terminal bottom portion, and c) the third edge segment connects the first edge segment and the second edge segment; and at least one affixing element joining the first edge segment of the first terminal bottom portion with the first edge segment of the terminal end portion, the second edge segment of the first terminal bottom portion with the second edge segment of the terminal end portion, and the third edge segment of the first terminal bottom portion with the third edge segment of the terminal end portion.