Designed by Ed Pegg Jr.;
this puzzle made by J. A. Storer 2007
from a 1961 Adams Co. Dad's Puzzle and two plexiglass L-shaped pieces.
(cardboard sleeve, metal tray, 6 plastic / plexiglass pieces, 3.75 x 3 x 5/16 inches)

From the starting position shown below, move the bottom 1x2 piece to the top (i.e., float the soap). Baxter's page on Pegg puzzles lets you play this game and indicates a minimal solutin of 43 rectilinear moves.



Further Reading
Baxter's Pegg Page, from: http://www.johnrausch.com/SlidingBlockPuzzles/pegg.htm