While a large spotlight lately has been focused on hackers getting into the Sony Playstation Network, it's valid to note that the most serious, consistent threats for most companies are phishing attacks that can compromise account passwords.
Phishing is the use of false but seemingly honest emails or messages to gain control of passwords and account information. The message typically asks the recipient to sign into an account. But the site being used is a ruse to gain the password information.
Once the phishing scam succeeds, the bad guys gain control of an account, usually to transfer money. The Spokesman-Review wrote about three prominent area phishing examples affecting three companies, in this 2010 story.
We're running this illustration, provided by ESET, a software and anti-virus protection developer. It notes that the United States is the leading country for sites that host phishing attacks.