I always imagine screen used props that were sold at auctions to be placed in a glass case under a spotlight in some millionaires house - only to be seen by him and the few guests that are allowed inside.
Sadly, I don't have any Pred props, but I do have a foam rubber stunt rifle from "Starship Troopers" and one of the stunt Roman Legion shields from "Gladiator". They're both hanging on my wall. I used the rifle as a prop in the fan film I am currently doing (titled "Predators: The Hunt"). I consider it sort of an homage to one of my favorite sci-fi films.