Where's it at?

I don't think I can be convicted of being a Grammar Nazi solely for my severe agitation with the word "at" placed at the end of a sentence, where it most certainly does not belong. So I have to tell you, I've had it. If I hear one more person say any of the following, I cannot be responsible for the words that emerge from my mouth:

• I can't remember where I left that paper at.
• Now, where were we at?
• Oh vacation! Where are you staying at?

Frankly, (and perhaps arguably), "at" poses the greatest violation of the "no prepositions at the end of a sentence" rule. Most of the time, the "at" is completely superfluous. Take the "at" out of any sentence above, and it's not only just fine without it, but it's far superior (not to mention proper).

No, you won't hear me say "With whom did they ride?" Although technically correct, it's a little stuffy. The use of "at" as the final word, however, is totally uncool. I have noticed some people get so carried away with it, they might as well add it to every sentence.

In short, at is abused at great lengths at attempts to add extra words where they shouldn't be at.