Algodoo

5 different configurations of springs, attempting to remove as much rotation as possible.

Lower right - high strength.
Lower left - low target length.
Middle right - high target length, weak.
Middle left - high target length and strength
Top - Negative values for target Length.

Contacts with default box:
Bottom Left - Falls.
Bottom Right - Deletes itself and the box.
Middle Left - Deletes itself and the box.
Middle Right - Falls.
Top - Falls.

Rotational Force:
Top - Peak at 40rad/s or so.
Middle Right - Peak at 450rad/s or so.
Bottom Right - Peak at 110rad/s or so.
Bottom Left - Peak at 800000000000rad/s or so.
Middle Left - Peak at 1300000000000000000000000000000rad/s or so.

Conclusion: Negative Target Length is most effective.