The speed, size and dependability of programming languages
The Computer Language Benchmarks Game is a collection of 1368 programs, consisting of 19 benchmark reimplemented across 72 programming languages. It is a fantastic resource if you are trying to compare programming languages quantitatively. Which, oddly, very few people seems to be interested in doing.
The Benchmark Game spends a lot of efforts justifying itself against claims that the benchmarks are always flawed and that the whole exercise is pointless. I don't think it is. In fact, I've found that The Game is remarkably effective at predicting which forum hosts programmers annoyed at the slowness of their language, and that's good enough for me.