My brother did it. It cost him a ton in electricity and he didn't get much from the machine. However, his friend made about 20k. He got into the game much earlier though.
Another dealer I've liked is bullionexchanges.com. All three are great companies to buy and sell from! Apmex has a great rep but I often find better deals at Bullion Exchanges.
You can always have them checked out by the two coin grading services (PGCS and NGC) or a dealer like Bullion Exchanges. At least you'll know if it's worth something or not. Either way, awesome coins for a collection!
If I won that much, I would buy silver from a dealer like bullionexchanges.com and a ton of gold. Any suggestions on what's best to get according to this group? Then just continue to stock up on other things. It would be hard to imagine trying to spend that much but fun!