The work that Machiavelli is most famous for is titled "The Prince," though it was not published during his lifetime.  The reason why it stood out at the time it was published was because it was one of the first treatises on leadership or political science that focused on something along the lines of the ends justifying the means.

Instead of focusing on things like being righteous or whatever moral principals many ideas about leadership focused on at the time, his philosophy was pragmatic, how does one go about achieving the desired effect through the most efficient method/means possible.

So the term "Machiavellian" came into being, and current examples would of course depend on your perspective, but if you are, for example, a person who feels that regulation and any rules on finance are bad things, using the revolving door to government to further those aims as Hank Paulson and others have done would be a great example.  It might not look effective at the time, but in the end has been hugely beneficial to him, his interests and his friends.