[What is that Euro doing to that dollar?!]

We've all been hearing how cheap the US Dollar is these days. Some of us have experienced it, or seen Europeans scoop up Manhattan real estate like its going out of style. But most of us don't understand it. Why is the dollar so cheap, what's causing such a massive reduction in purchasing power parity? I'm not a finance jock, so I often look elsewhere for answers. Economic wonks have a myriad of reasons, but sometimes looking at the larger picture, and focusing on the macro level is the most lucid way of understanding these questions.