I don't usually bring this "gift" of mine up in real life, it tends to create pretty awkward and unpleasant situations.

"Oh, if you have such sharp sense of smell, then tell me what deodorant/lotion/perfume I'm using?" How the hell could I know the names of every hygienic/cosmetic product, especially when the reek of detergent, fabric softener and sweat is mixed with the scent I'm supposed to recognize?

Or people just laugh at me and call me a liar.

But my friends are aware of my talent, when someone is considering to buy an apartment they often ask me to accompany them for a presentation. I can tell almost instantly if there's water damage or mold. When I was buying my own apartment I found one spot under the stairs that had a very faint but odd smell, like wet cement mixed with the smell of a wet dog. There were no water pipes or sewers even near that wall, nor were there any signs of leaks from above. I called the seller to ask about this and he started laughing. The spot was their old dog's favourite place to curl up for a sleep after a walk in the rain. And it was years since the dog had passed away, they had even painted the wall once and renewed the floor laminate after that. So no worries, I bought the place.