Madonna at 40: The new face of Max Factor.

Just as soon as we figure out who Madonna is, she reinvents herself once more.

At 40, the idol still worshiped by teenage wannabes the world over and who exhibited her shapely self in a soft-porn coffee table book called "Sex," is now - (drum roll, please) - the new face of Max Factor!

Brit newspapers yesterday previewed images from a commercial starring Madonna that the beauty house's publicists said is due to be shown on prime-time Brit TV Friday and in Europe and Asia this summer.

In her latest transformation, the Material Girl looks enigmatically at the camera through a gold net butterfly mask, all flawless foundation and deep plum lips in a posethat was the rage in the 1930s. …