guns4pennies
They're not like a normal auction site, but it's legitimate. They're a penny auction, like beezid.
Penny auctions definitely aren't for everybody, and it's possible to spend cash without winning anything, but you can also get some great deals. I've won several things there, and actually just won an HK MR556A1 last week. Just takes a combination of luck and skill.
And they're actually out of Baltimore, not Chicago. I think that's just where their server is located.
Below is the description of how this type of business works from their facebook page.
Penny auctions work like this: Users purchase packages of bids. Depending on how many they buy at a time, the bids cost between $0.97-$0.68 apiece on G4P site. During an auction, the timer counts down, but anytime someone uses a bid it is deducted from their account and the timer is reset to 30 seconds. If the timer reaches 0, the last person to have placed a bid gets to purchase the item for that price. In this type of auction, both the user and the business are taking a chance. The business takes a chance that enough people will have bid on an item (thus spending those 97-68 cents each time) that they will have covered the cost of the item and allow us to make a profit. The users are taking the chance that they will be the last person to bid, spending less than they would have to buy the gun or accessory in a normal manner. If they don't win the auction, they've still already spent the money to bid, but the possibility of winning an item fairly cheap is worth the risk to those who've decided to participate. Many also like the excitement that this type of auction brings. Some things you will see sell very very cheap. Those are the times that our chance didn't pay off and we lost money on the items. It happens fairly often. But overall enough people enjoy the auctions that they keep coming back and create a sustainable business.