Derrick Schneider uses the four trijogs to make his puzzle Square Dance.  fit the four pieces into either a 7x9 or 8x8 rectangle.  Both solutions are unique.  The puzzle was a prize-winner in the Nob Yoshigahara Puzzle Design competition. George Sicherman has enumerated polyjogs.http://www.recmath.org/PolyCur/polyjogs/  The 17 tetrajogs are easy to place into Burr Tools, and they can fit into a 20x20 square.  A 19x20 rectangle looks very doable, but Burr Tools wants a few hundred thousand years for that analysis.  Can anyone place the 17 tetrajogs into a 19x20 rectangle by hand? --Ed