Penny auctions are more like lotteries and slot machines than an auction. You won't really win anythere here more than you would if you went to a casino. Read about them from time magazine
http://www.time.com/time/magazine/article/0,9171,*******,00.html
And even a blog here on sitejabber
http://www.sitejabber.com/blog/2010/09/02/understanding-the-penny-auction/