Actually animal behavior specialists have debunked this. The cat is not bringing you a damned thing. The cat is well-fed, and therefor not hungry, yet still follows its instincts to hunt for sport. It proudly carries around its kill for a while until something else captures it's attention (very often that turns out to be their humans) and they just drop what was in their mouth wherever they happened to be. It's not FOR you; they just lost interest in it.