An assembly for cooling comprising: a folded sheet; wherein the folded sheet exhibits a beveled edge, at least a first fold, and at least a second fold; wherein the first fold and a first portion of the beveled edge form a portion of a perimeter to a first region; wherein the first fold, a second portion of the beveled edge, and the second fold form a portion of a perimeter to a second region, and wherein the first portion of the beveled edge is continuous with the second portion of the beveled edge; wherein the second fold and a third portion of the beveled edge form a portion of a perimeter to a third region, and wherein the second portion of the beveled edge is continuous with the third portion of the beveled edge; wherein the first region of the folded sheet is substantially flat, the second region of the folded sheet is substantially flat, and the third region of the folded sheet is substantially flat; wherein the first fold is separated from the second fold by a first distance; wherein the first fold is configured to present a first non-zero acute angle between the first portion of the beveled edge and the second portion of the beveled edge such that the second fold is elevated from the substantially flat first region by a value that is less than approximately one of a set of values consisting of: 0.5 mm, 0.45 mm, 0.4 mm, 0.39 mm, 0.38 mm, 0.37 mm 0.36 mm, 0.35 mm, 0.34 mm, 0.33 mm, 0.32 mm, 0.31 mm, 0.3 mm, 0.29 mm, 0.28 mm, 0.27 mm 0.26 mm, 0.25 mm, 0.24 mm, 0.23 mm, 0.22 mm, 0.21 mm, 0.2 mm, 0.19 mm, 0.18 mm, 0.17 mm 0.16 mm, 0.15 mm, 0.14 mm, 0.13 mm, 0.12 mm, 0.11 mm, 0.1 mm, 0.09 mm, 0.08 mm, 0.07 mm 0.06 mm, 0.05 mm, 0.04 mm, 0.03 mm, 0.02 mm, and 0.01 mm; wherein the second fold is configured to present a second non-zero acute angle between the third portion of the beveled edge and the second portion of the beveled edge such that the second non-zero acute angle is approximately the first non-zero acute angle; wherein the folded sheet is configured to present a series of channels for a flow of gas, optionally wherein the gas comprises air. a folded sheet; wherein the folded sheet exhibits a beveled edge, at least a first fold, and at least a second fold; wherein the first fold and a first portion of the beveled edge form a portion of a perimeter to a first region; wherein the first fold, a second portion of the beveled edge, and the second fold form a portion of a perimeter to a second region, and wherein the first portion of the beveled edge is continuous with the second portion of the beveled edge; wherein the second fold and a third portion of the beveled edge form a portion of a perimeter to a third region, and wherein the second portion of the beveled edge is continuous with the third portion of the beveled edge; wherein the first region of the folded sheet is substantially flat, the second region of the folded sheet is substantially flat, and the third region of the folded sheet is substantially flat; wherein the first fold is separated from the second fold by a first distance; wherein the first fold is configured to present a first non-zero acute angle between the first portion of the beveled edge and the second portion of the beveled edge such that the second fold is elevated from the substantially flat first region by a value that is less than approximately one of a set of values consisting of: 0.5 mm, 0.45 mm, 0.4 mm, 0.39 mm, 0.38 mm, 0.37 mm 0.36 mm, 0.35 mm, 0.34 mm, 0.33 mm, 0.32 mm, 0.31 mm, 0.3 mm, 0.29 mm, 0.28 mm, 0.27 mm 0.26 mm, 0.25 mm, 0.24 mm, 0.23 mm, 0.22 mm, 0.21 mm, 0.2 mm, 0.19 mm, 0.18 mm, 0.17 mm 0.16 mm, 0.15 mm, 0.14 mm, 0.13 mm, 0.12 mm, 0.11 mm, 0.1 mm, 0.09 mm, 0.08 mm, 0.07 mm 0.06 mm, 0.05 mm, 0.04 mm, 0.03 mm, 0.02 mm, and 0.01 mm; wherein the second fold is configured to present a second non-zero acute angle between the third portion of the beveled edge and the second portion of the beveled edge such that the second non-zero acute angle is approximately the first non-zero acute angle; wherein the folded sheet is configured to present a series of channels for a flow of gas, optionally wherein the gas comprises air.