If you work in a library and want to freak yourself out, read NYU’s studies on contagion rates of various printed materials. (I saw this after going through about two book carts full of stuff. Aieee!) 

If you excel at grammar and know others equally as persnickety, get yourself (safely) together for a few rounds of Stet! It’s a game which would be a perfect warmup to a proofreading test (and I just agonized over whether it should be “that” or “which” before deciding it didn’t matter that much). 

Fun futuristic news: Holographic menus are here! No word on whether proofreaders are necessary.