The Business On... Mark Gorton, Founder, LimeWire

Is that still going? I can't get the website to work these days.

That's because the company was slapped with an injunction last October forcing it to stop distributing the software that had enabled music fans to download songs for free.

So what's happening now?

Mr Gorton, the founder and owner of LimeWire, is facing several music companies in a court battle. The case began yesterday, with the music industry demanding he pay them damages of as much as $1.4bn (£850m).

Isn't that rather draconian?

It's fair to say there's some bad blood with this one. When Mr Gorton launched LimeWire a decade ago, there were a string of similar "peer-to-peer" music services on the internet. But while all the others shut down in the face of music industry legal action, or at least went legitimate, Mr Gorton held out. The music industry hates him for it.

Why was he so obstinate?

It depends who you believe. Mr Gorton says he was naive about the legal issues, while the music business accuses him of greed.

Is there anything else going on?

Well, Mr Gorton is a man who sticks to his principles. He's a committed campaigner on environmental issues who has given substantial financial backing to American groups that support greener means of transport, such as cycling. He's also launched a technology project that encourages green urban planning.

He doesn't sound like the sort of man who has $1.4bn?

Who does? But actually, Mr Gorton has made substantial sums from LimeWire. And having started out as a trader with Credit Suisse, he knows a bit about finance: he runs his own brokerage firm as well as LimeWire.

Still, he can't pay, surely?

Not $1.4bn or anything like it, but the court could rule he owes damages of as little as $7.2m, which might be more manageable. But expect the music companies to go for blood – they are already accusing him of having rearranged his finances to hide some of his wealth.