In the car park, Porsches and Mercedes rub shoulders with Range Rovers and, inside, the founders of YouTube and Bebo mingle with the bosses of Orange, BSkyB and Google.
It is Google that has brought all these powerful people together. It is a measure of the respect - and fear - that the megalith of the new media world inspires that it can summon such a collection of movers and shakers to Hertfordshire.
They are spending two days debating everything from serial entrepreneurship to new technology in the developing world. But just as importantly they are here to network.
Next big thing
In one corner, Environment Secretary David Miliband is updating his blog after addressing the conference.
In another, lastminute.com founder Brent Hoberman - a veteran of the first dotcom bubble - is chatting to Tariq Krim, founder of Netvibes, a web 2.0 start-up.
The event is called Zeitgeist. So what can we learn about the spirit of the times from this gathering?
Well, it's clear that the big old media businesses in attendance - BSkyB, Germany's Axel Springer group and, yes, the BBC - are desperate to work out where the next new idea is going to come from.
So they are very keen to hear what the likes of YouTube co-founder Chad Hurley have to say.
We allowed the community to tell us what was entertaining them
Chad Hurley, co-founder of YouTube
When I catch the jet-lagged video-sharing pioneer and ask him what'll be the next big thing, he laughs and says: "I know, but I can't tell you."
Not surprising really. After all, the big idea he thought up just two years ago has made him unimaginably rich.
Today, he tells the Zeitgeist gathering, six hours of new content is uploaded by YouTube users every single minute, and more than 100 million people are viewing the videos.
The secret to his success? Putting the right technology out there to meet an unfulfilled need - sharing videos online.
"We needed it to be a no-brainer to upload," he explains.
The other innovation was to let users make the decision about what was worth watching.
"We allowed the community to tell us what was entertaining them."
But Chad Hurley is now keen to see traditional media companies using YouTube as a platform.
He seems unfazed by the fact that those old media businesses seem more inclined to sue YouTube rather than play ball. But he can afford to be relaxed after selling the business to Google last year.
Massive server farms
The virtual world of Second Life - and its potential as a marketing tool - is another business which generates a buzz at any new media event.
It is mentioned in just about every presentation at Zeitgeist - despite the fact that its active users are far fewer in number than those playing online games.
The next movie is not the same as the last movie
Eric Schmidt, Google chief executive
But Robin Harper, from Second Life's developer Linden Lab, reveals that many users are now spending 80 hours a week living and working in this virtual world, and last month its economy generated $45 million in real hard cash.
"A virtual world can help you communicate with your customers," she tells the conference.
The most powerful player talking here was Google's own boss Eric Schmidt.
He flew in for a "fireside chat" and revealed that he is worried about the perception that Google is the new Microsoft - but sure that they are very different businesses. "The next movie is not the same as the last movie," he insisted.
He also admitted he was puzzled that nobody had managed to imitate Google's AdSense technology and is convinced that the future is all about mobiles and cloud computing, where all the world's data is stored on massive server farms.
Like everyone else at this conference, Mr Schmidt is betting huge sums on where the web will head next.
But if YouTube is anything to go by, the future is probably being built right now by a couple of young men in a garage.