Purchased from ThinkFun 2006. (plastic, 6 pieces, 2.75 inches)

Made by D. Alsmeyer 2007, Sabriday Puzzles. (6 different woods, 3.5 inches)

The booklet that comes with the retail plastic puzzle shows 65 steps to completely take the puzzle apart. McFarren's Page shows a solution that removes the first piece in 28 steps, and completely takes the puzzle apart in 35 steps.

Further reading:
McFarren's Page, from: http://www.geocities.com/abcmcfarren/math/gordian.htm
Sabriday's wood description (Mahogany, Maple, Cherry, Purpleheart, Walnut, Paduk).