I'd also recommend a good game of arXiv vs. snarXiv: http://snarxiv.org/vs-arxiv/

As a non high-energy physicist, it's surprisingly hard! I usually do _worse_ than random chance, sometimes substantially so.

The author also has perhaps my favorite definition of a CFG: "The snarXiv is based on a con­text free gram­mar (CFG) — basically a set of rules for computer-generated mad libs."