Facebook hopes to raise as much as $13.6 billion in an initial public offering of stock, probably in mid-May. It would be the largest IPO ever for an Internet company. Here are the top 10, according to Renaissance Capital, an IPO investment adviser: 
 -  Google: $1.67 billion, 2004
-  Yandex NV (Russian search engine), $1.3 billion, 2011
-  Infonet Services Corp (now part of BT Group PLC), $1.08 billion, 1999
-  Shanda Games, $1.04 billion, 2009
-  Zynga, $1 billion, 2011
-  Giant Interactive Group, $887 million, 2007
-  Renren, $743 million, 2011
-  Groupon, $700 million, 2011
-  Orbitz, $510 million, 2007
-  BarnesandNoble.com, $450 million, 1999