From the 628weeks.com site:

"The NuclearMouse plugin currently enables you to do three things:

Drag/move windows by clicking anywhere on the window.

Resize windows by clicking and dragging anywhere in the window.

Adjust the transparency of the window.

The first two features are enabled via a user-customizable modifier key + mouse button combination. The currently allowed modifier keys are control, command, and option. The available mouse buttons are left, right, and middle. If you have a 3-button mouse, then I recommend mapping these commands to the middle mouse button and they don't appear to be used for much else in MacOS X. The last feature is tied to the scroll wheel. If you use a laptop, two-finger scrolling accomplishes the same thing."