Every day, there seems to be a headline about some type of online security breach. Just look at the recent denial-of-service attacks at Twitter and Facebook. Yes, it seems that no one is immune from the perils of the electronic world.

Interestingly enough, this is good news for ArcSight (NASDAQ: ARST), which develops a variety of security solutions. To get a sense of this, look at the company's fiscal Q1 results (which came out Thursday).

With President Obama highlighting the national importance of cyber security, we turn to technology specialist Gregg Early to find the best investment ideas in the sector.

Noting that "cyber security is one of the biggest new sectors in the information technology industry," the editor of Personal Finance offers a trio of buys in the field -- McAfee (NYSE: MFE), Versar (AMEX: VSR), and Unisys (NYSE: UIS).

The advisor explains, "In exchange for an annual fee, McAfee allows users to download the basic security software and regular updates. These frequent updates are essential because virus and malware threats are constantly evolving.

The Washington Post reported over the weekend that the CIA had warned U.S. utilities of the possibility of attacks, or threats with extortion demands, via the internet. At a conference in New Orleans attended by security officials from governments, utilities, and companies such as Chevron Corp. (NYSE: CVX) and BP (NYSE: BP), a cybersecurity analyst broke with CIA disclosure polices to detail several recent cyber intrusions outside the United States, one case resulting in a power outage that affected several cities.

Increasingly sophisticated intrusions into corporate computer systems have cost companies worldwide more than $20 billion each year, according to some estimates. And extortion is a growing threat, with attackers radically increasing their take from online gambling sites, e-commerce sites, and banks, which pay up to prevent their sites from being shut down and to avoid public knowledge their sites have been hacked.

With the rising tide of cyber attacks on the infrastructure over the past year or so, and the vulnerability of the power grid, transportation systems, and big banks becoming increasingly clear, investors have to wonder how secure the exchanges are from extortion or efforts to manipulate the markets by individuals or organized groups. The London Stock Exchange suffered a cyber attack this past June. Such attacks frequently originate from overseas, sometimes supported by foreign governments, and perpetrators can be next to impossible to track down and bring to justice.