I have a puzzle not in your list; it's rare enough that I've never seen
it in a store or catalog. I got mine from a friend. He calls it "The
Barrel".

Imagine a transparent cylinder divided into 6 circular slices. Slices 2-5
each have 5 pockets equally spaced around the circumference, just below the
surface (see left figure below). Slices 1 and 6 have three pockets in
positions corresponding to 3 of the 5 (see right figure).

       *******       		       *******       
     ****   ****     		     ****   ****     
    *****   *****    		    *****   *****    
   ******   ******   		   ******   ******   
  *****************  		  *****************  
 ******************* 		 ******************* 
 ******************* 		 ******************* 
*   *************   *		*********************
*   *************   *		*********************
*   *************   *		*********************
*********************		*********************
*********************		*********************
*********************		*********************
*********************		*********************
 ******************* 		 ******************* 
 ***   *******   *** 		 ***   *******   *** 
  *    *******    *  		  *    *******    *  
   *  *********  *   		   *  *********  *   
    *************    		    *************    
     ***********     		     ***********     
       *******       		       *******       

Through the center of the cylinder runs a piece with a cap on each end.
The caps each have 3 prongs poking into the cylinder, lined up on the
3 openings in slices 1 and 6. However, the central piece is long enough
that if the prongs are pushed into slice 6, the prongs at the other end
are lifted out of slice 1, and vice versa. So, at any given time, three
of the end pockets are filled by one of the endcaps. The other 23 pockets
contain colored balls.

Originally, the 3 balls in the unpronged endcap are black, and the balls
in the other slices are lined up by color; i.e. 4 blue balls lined up
above one another in slices 2-5, 4 green balls, likewise lined up, etc.
The possible moves are:

1) Slide the endcaps up and down. E.g., from the starting position, this
would push three balls of different colors into slice 6, and push the 3
black balls from slice 1 into slice 2 (and also push various balls of the
same color down, but that has no visible effect).

2) Turn slices 2 and 3 together; they do not move separately.

3) Turn slices 4 and 5 together; ditto.

Slices 1 and 6 are fixed, so they always line up with the end cap prongs
and with each other.

That's all there is to it. It certainly has the "cubish" feel to me, in
that it's impossible to make single moves that affect only a small portion
of the puzzle.

-- Don.