I received the 5th edition of Singmaster's booklet a few days ago, from Logical
Games, Inc.--presumably they have some $4 copies left (they sent mine 1st
class mail)....Bela Szalai (LGI) loaned me a 2x3x3 to play with. Conceptually,
of course, it's the same as the 3x3x3 with moves restricted to <U,D,F^2,R^2,
B^2,L^2>...physically, however, it was MUCH less aesthetic to play with...
turned poorly, and looked ugly. Bela had a couple of them, both of which
were rather more "delicate" than the 3x3x3 (in that they tended to get jammed
or come apart). -- Mark