Making a pendulum?

Using hinge joints, how can I make a pendulum (I want to make a bionic commando style swinging effect)? I want to have something like this, where the player is able to shoot out a hook, have it anchor to a part of the level geometry and then swing on it, while being constrained to 2D movement. The swinging does not have to be very complex.

EDIT I have expanded on my question here

You might want to check out this video: http://vimeo.com/7886895

It is a good intro to making swinging objects (wrecking ball), but I think you can easily adapt it for your needs. Best of luck!

I created a tutorial with the Euler-Cromer method to simulate a simple pendulum.

make a rigidbody and attach a part of it (with joints) to the axis that you want it to rotate.

Well im not sure im nooob but I think it may work :D