A while back a mechanic was working on my car and handed this piece to me saying that it fell off but it doesn't serve any purpose. I'd like to try putting it back but I have no idea what it does or where it goes. Any idea?

 

I don't know what it is but you'll have better chances of someone knowing what it is if you can list more info about your car and what or where about was your mechanic working on. To me it looks like something that belongs around the front bumper but I'm sure that I'm way off lol

 

Looks like it might be the spoiler off the driver's side windshield wiper:

 

Thanks a lot. Windshield wiper makes sense since I knew they were replacing the wiper blades among other things. Thanks again.

 

That was my first thought as well... It's the anti-wind-lift wing from the driver's side wiper.

Spridget