By BBC News Online's Alfred Hermida

The next time you install software on your computer at work, you could be facing criminal charges.

This is what happened to computer technician David McOwen, when he installed a program on the PCs at DeKalb Technical College in Atlanta, Georgia, US, without first asking permission.

Mr McOwen loaded a distributed-computing program, similar to the Seti@home screensaver, on the college's PCs so that spare computing capacity could help in a volunteer code-breaking challenge.

For his actions, he was charged with computer theft and computer trespass, facing a fine of up to $415,000 and anything from eight to 120 years in jail.

'Good intentions'

Throughout the case, Mr McOwen maintained he did nothing wrong.

McOwen: Jobless at the moment

"There's a very large difference between people who go out and do crimes on purpose versus someone who is innocent and has good intentions and you get attacked under the law," he told the BBC's Go Digital programme.

"They said it was one of the worst things the state had ever seen in regards to computers and crime."

But the case never went to court as earlier this month Mr McOwen accepted a plea agreement to end his two-year legal nightmare.

Under the terms of the deal, he walked away with probation, a small fine and community service.

Power going to waste

The story began in 1999, when David McOwen worked on the computer systems at DeKalb Technical College in Georgia.

This has been proven as a technology for the betterment of mankind on a worldwide scale

David McOwen

He realised that most of the machines on campus sat idle most of the time, with good computing power going to waste. So he installed a program from distributed.net on the PCs.

"If it is in screensaver mode, the computer is just sitting there, wasting electricity, whereas it could be being used to help mankind in a small way," he said.

Georgia state prosecutors had initially sought more than $415,000 in restitution for bandwidth charges, calculated at 59 cents per second based on the number of machines and amount of time involved.

"It's not an abuse of PCs," argued Mr McOwen. "This has been proven as a technology for the betterment of mankind on a worldwide scale."

Legal precedent

Hundreds of thousands of people run distributed computing clients at private companies, universities and their homes. The most famous one is the Seti@Home screensaver programme.

Distributed computing works by chopping up large computer jobs into small portions, and sending these bits of work to individual PCs over the internet.

The case has sent shivers through the distributed computing community, with many concerned that it has set a legal precedent.

Last year, the Tennessee Valley Authority sacked 18 employees for running Seti@Home on their computers. They were threatened with criminal charges, but that never came about.

Mr McOwen sees the end result as a victory. "This is really a defeat for the statute, not a win, because it shows the statute needs fine tuning."

The case has taken a heavy personal toll on the system administrator. He resigned from his job at DeKalb soon after the school threatened him and last August he was fired from his next job because of the bad publicity surrounding the case.

He has been jobless for several months and has been surviving on his wife's salary and help from his father.