The botnet takedown announced Wednesday by the U.S. Department of Justice was the biggest in history, a security company says. The collection of compromised computers numbered over four million machines. Seven men — six Estonians and one Russian — were charged with 27 counts of wire fraud, money laundering and illegal computer access. The FBI shut down over 100 domain and botnet command-and-control (C&C) servers in New York City and Chicago. The malware responsible for hijacking users’ clicks came in a variety of forms.”]