You know, I don't generally know about the age of folks on here, but with questions like this one here I pray to Zeus you're young and can still change your ways. Or at least travel, see the world, see some people starve and die, just to put things into perspective.
I picked the 'Depends on where I dropped the food', as that's usually my most important deciding factor. At home, I've repeatedly pretty much eaten off the - clean - floor to train puppies and kitten and kids. Outside, in the woods, on the lawn, it's all good. In the streets with lots of dirty people and shoes and human waste and boogers and sweat and blood and tears sticking to everything, nah, not so much.
It also depends very much on the food in question and the state it's in. Raw meat that's about to get fried in the pan? Sure, just rinse it and clean it first. No harm done. Stuff that's about to get boiled? Meh, depends. If it's just for myself, absolutely, if it's for hungry hungry hippos or other pet animals, absolutely, if it's for guests or freshly hatched human babies... probably not, no.
The n seconds / minutes / lightyears rule is complete and utter bollocks. If I were to stick my finger in random poop, it does not matter how long I held it in there to make it quite unsanitary. If the floor in question is reasonably clean and the food is dry, eating it is a no-brainer. If the food gets heated up quite a bit, it's a no-brainer. If the food maintains its consistency and shape, it's a no-brainer. I wouldn't eat raw eggs off the floor and I wouldn't eat liquid foodstuffs off the floor, and we're all quite healthy and easily seem to resist the various flu-like influenza waves without any vaccination whatsoever, so I don't think living a germ-free life is necessarily a good thing, quite on the contrary. I also have an intolerance when it comes to hair. Just thinking about hair or toenails or bellybutton fluff sticking to things is enough to make me projectile vomit, so that's out of the question.
The last thing I ate off the floor was 1) a delicious little snippet of pig that fell on the kitchen floor while I was cutting it up prior to being marinated and pan-fried and 2) a crisp that I sent flying due to some surprise fumbling on my behalf. I'm less tolerant when at somebody else's place.
Just this morning, I dropped a raw egg in the kitchen. I did not eat that. Had the egg already been cooked and firm, I would absolutely have eaten it. I still fried it up immediately and gave it to the cockroaches, a rare treat that's healthy to them and, in turn, makes them strong and healthy and superiour food to the lizards and spiders.