The 6x10 rectangle has 2339 solutions, and some of them have special properties, such as:

• Contain a 3x5, 4x5, or 5x6 rectangle,
  in different positions and orientations.
• Contain a symmetric region which can be flipped.
  Some have two !
• Contain two congruent regions which can be switched.
• Have a minimum (8) or maximum (12) pentominoes touching the edge. (There are just two of the latter.)

There are many ways the 6x10 can be divided into two congruent parts. Here are a few of them. How many can you solve ?
Which others can you find ?
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