A WW2 re-enactor supply house called At The Front sold uniforms, field gear and plastic weapons from "Saving Private Ryan" at downright ridiculously cheat prices, even then. I bought some of the stuff but I really wish I'd bought an awful lot more. It was all so cheap, people were buying the stuff and modifying it to use in re-enactments.
I've also had the chance to buy, but turned down:
*Complete Imperial soldier uniform from the crew of War Rocket Ajax from "Falsh Gordon"
*"Total recall" federal guard helmet for just $40 (I still wonder why I didn't snatch that up)
*"Planet of the Apes" rifle housing
*"Band of Brothers" complete T-5 parachute
*"Space Cowboys" space shuttle liftoff-entry suit (I passed because I thought at the time it was probably stolen from the production, now I wonder if it was really from the movie at all)
*"Memphis Belle" (1990 movie) screen-used A-2 jacket
*ROTJ Stormtrooper armor pieces, found by a friend of mine while picking through the California 'Endor' filming site, confirmed by three other friends of mine that saw as he stumbled across them all in one spot
*Apollo space suit from the TV series, "Space"
*"The Story of GI Joe" Burgess Meredith's 'Ernie Pyle' field jacket. It was NOT cheap but man I regret not biting the bullet on that
*BUT MOST OF ALL: "Aliens" screen-used pulse rifle complete metal housing, only missing the shotgun and Tommy gun. I missed that one because the guy wanted a small fortune and I didn't have the money but man do I wish I'd been able to buy that...