Scientists have discovered a man-sized fossil of a dinosaur that is essentially a 1/100th scale model of a Tyrannosaurus Rex. From the Smithsonian's website:

In this week’s edition of Science, an international team of scientists describes a new, diminutive precursor to the more familiar Cretaceous giants. It was discovered in approximately 130-million-year-old rocks in China. They have named it Raptorex kriegsteini.

At first glance you could be excused for thinking that Raptorex was the juvenile stage of one of the later tyrannosaurids. At only about 10 feet long, it had long, gracile legs, a slender-looking head, a large eye socket, and ridiculously small forelimbs which terminated in claws. While it was not quite a fully mature individual, it was not the juvenile stage of an already-known dinosaur. It was something scientists had never seen before, one that can tell us much about how its giant cousins evolved.