Some business owners feel spyware is the biggest threat suddenly:
Spyware. Servers can be taken down - and rebuilt. Spam spewing out of servers is a big nasty pain. If someone takes over a server that is really bad because they can divert your revenue and steal your source code.
But spyware seems like the evilist of evils. Why? Because with spyware someone can do all of the above easily and more. With spyware someone can log all your passwords - like when you log into your online banking site or your server or VPN. Spyware can potentially allow reading any communications you are sending so someone can know what you want and are going to do before the third party to whom the message is being sent. For instance are you sending a quote? They can undercut your bid easily and woo your potential customer.
With spyware a hacker can learn about your infrastructure and potentially find ways to intercept, block and change messages in transit. I am not 100% certain how much of this is possible or why or why not -- but don't tell me it is not possible because hackers find a way to do everything.
If you know you have a hacker on your system and use your computer in any way to communicate about it, they can read it. A great engineer I knew who worked at Excite way back in the day said they were fighting a hacker and called him some name in an email communication. They then all got a response "My name is Jim".
How can you fight someone who knows your every move? Spyware is the ultimate cyber evil and cyber espionage tool.
And these days, hackers are more crafty and harder to spot than ever, so I could be sitting here typing this while some guy in Russia is reading every letter using a keylogger. How should I know?