I came across a neat website, Hyperpolyglot, the other day that does a really good job of showing off the differences in various programming languages in a side-by-side way. So for instance you can see how to do the same sort of thing in C++, Objective-C, Java and C# all right next to one another. Take a look and compare your favourite languages here.
I stumbled upon a really interesting website tonight run by the guys behind the Debian project. Essentially it is a series of programming language benchmark results, run under different configurations, that not only shows you how each language performed, but also lets you compare and contrast them to one another. So for instance I can compare the performance of C and C++ running on x64 Ubuntu with an Intel Q6600 quad-core.