I am especially angered by Goggle [sic] Plagiarism, because the act implies that the professor (me in this case) is too stupid to figure out what's going on. That's why my syllabus now contains the following very direct warning on academic honesty:

If you cheat, I’ll catch you. Guaranteed. Resist at all costs the temptation to download or copy entire papers or large sections of research. Not only have I read extensively in the usual sources, but I also have an excellent idea of your writing abilities and styles, and can tell when students are not using their own words. If you’re caught cheating, you’ll fail the class.

Pretty direct, no?

So perfectly direct and perfectly clear that none of those I caught cheating (including an officer of the History Club, a junior who should have known better) could deny the meaning of my policy. Nor could they reasonably appeal the "F" they earned by their behavior. [...]