1) A toenail - Any nail is bad, but a toenail is the absolute worst. So many questions arise from it, such as: why was someone cutting their toenails in the restaurant? And, who carries toenail clippers while working (assuming they didn't go all crazy and use fingernail clippers instead).

2) Boogers - This is an obvious choice. While kids are often seen eating boogers, we're going to assume that nobody eating a burger would want a booger in their food (especially if it's not their own).

3) Rat droppings - Okay, so you got feces in your burger, it happens. But what's worse is there are probably rats in the establishment. Who wants to eat with rats?

4) Broccoli - This choice may not be as gross as other selections, but who in their right mind would want broccoli in a hamburger? You wouldn't. Even a vegetarian wouldn't wish for it (of course, they probably wouldn't be eating a hamburger anyway).

5) A coupon - Coupons can provide great savings, but you don't want to find them in a nice juicy hamburger. What's worse, if you accidentally swallow the coupon you'll have to wait 1-2 days before you can actually use it. Everyone loves a good deal, but not when you have to go "fishing" for it.

6) Tears - Someone crying into your hamburger meat is better than other bodily fluids we can think of, but it's still sad. Why is the employee crying? Do they have a broken heart? A dead-end job? Maybe they misplaced their broccoli snack and are overly emotional over it?

7) Cat - Cats may be an acceptable meat at certain Chinese restaurants, but there is no excuse for using cat meat in a hamburger. You may like catsup on your burger, but catsup with catburger? That's in poor taste.