OK, so in addition to being able to get cheap hi-caps and tricking out my post-ban rifles and shotguns, here's an interesting tale for you:
Just as the ban went into effect back in 94 I added another pre-ban to my safe. It was a Colt MT6721, marked AR15A3 Tactical Carbine. At the time my dealer told be very few were made before the ban and was charging the high price of $1,500 for the gun.
Never shot it much - deciding that all of my pre-bans where too valuable for regular range and field shooting (I had set up 2 prebans as HD/SHTF rifles).
Fast forward to a few months ago. Realizing that the value of 6721s had grown a LOT and if the AWB sunsets the gun would be worth less than I paid for it 8 years ago - I decided to sell it.
So I posted it on the net and sold it for $4,800 in LNIB. Used the monies to help pay for an M16. Boy am I glad I sold it before the Republicans started making wind of letting the ban sunset!