HBGary Federal CEO Aaron Bar has resigned, doubtless cheering members of the elusive "hacktivist" group Anonymous who have targeted him in the past month. The hacker group gained wide attention last year with its large-scale attack on e-commerce companies that severed ties with WikiLeaks. In February, the group turned its attention to Barr after he told the Financial Times his plans to reveal the identities of its leaders.

In response, Anonymous members hacked HBGary Federal's website and unleashed 71,000 internal company e-mails, including one revealing that Barr's wife had threatened to divorce him. They also hijacked Barr's Twitter account, changing his profile photo and announcing that he was, in fact, a "sweaty ballsack of caterpillars."

But that was just the beginning. As journalists picked through HBGary Federal e-mails it became apparent that the company was offering to sell services to Bank of America and the U.S. Chamber of Commerce that were possibly illegal. Among other things, the firm proposed creating fake online identities to infiltrate and discredit progressive groups such as U.S. Chamber Watch.

Now, as Barr steps down from his post, House Democrats are calling for an investigation of HBGary Federal's "use of subversive tactics" to target progressive groups.

"The emails and documents that have come to light thus far provide a window into a deeply concerning set of circumstances," reads a letter Democrats sent to Republican House leaders. "The published correspondence appears to reveal a conspiracy to use subversive techniques to target Chamber critics... We believe it is therefore incumbent upon the Committee to investigate this matter thoroughly and with the utmost urgency."

In order for an investigation to proceed, House Republicans would have to get on board (rather unlikely). Nevertheless, Anonymous's clout is becoming increasingly hard to deny as elected officials take up its cause. And as for its ability to intimidate, Barr's comment to Forbes earlier this month speaks volumes.

"Do I regret [making those claims] now? Sure," he said. "I'm getting personal threats from people, and I have two kids. I have two four-year old kids. Nothing is worth that."