a.k.a. Snake Cubes, Serpent Cubes
Same idea as Kev's Snake Cubes, but a different pattern.
(2 inches square)

The Cubra Cubes are the same idea as Kev's Snake Cubes, but come in a number of different patterns; this is the first pattern shown on Mark Weston's Page:

"A solution can be described by a string of "directions" that the cube follows when you wrap it into a cube, either Right, Left, Up, Down, Forward, or Back. So for example if a solution starts R R F L ... then put the end of the snake with the rest trailing off to the Right, then the next cube goes in the same direction (it must be a straight-through cube), the next cube (a corner cube) turns to point Forward, then it goes Left, etc."
Solutions:
R R F L U U F D D R U B B L L F D F U U B B R R F F
R R U L F F U B B R F D D L L U B U F F D D R R U U"

Unlike Kev's Cubes, a solution starts and ends in the corners, and is not unique. Here is a solution that is provided for the Lagoon version of this puzzle (the same as the first one above, with the directions R-L, F-B, U-D all reversed):



Further reading:
Mark Weston's Page, from: http://www.cs.uvic.ca/~mweston/snakes.html
Lagoon Solution, from: http://www.give-me-a-clue.com