Grant Snider over at Incidental Comics offers up a slew of new proofreader's marks for consideration. I happen to be down with all of them, especially the cyclopsis, horribly wrong font, and word tornado options.
While many of us were taught in school, at least those of us of a certain age, that a sentence should never be ended with a preposition, that's probably a philosophy that has carried over from Latin grammar and isn't really suited for modern English usage.